WorldWideScience

Sample records for cell system based

  1. Fuel cell based hybrid systems

    OpenAIRE

    Davat, B.; Astier, S.; Bethoux, O.; CANDUSSO,D; Coquery, G.; DE-BERNARDINIS, A; DRUART, F; Francois, M; GARCIA ARREGUI, F; Harel, F.

    2009-01-01

    This paper presents different works which are currently developed in the field of fuel cell hybrid systems indifferent public laboratories in France. These works are presented in three sections corresponding to: 1. Hybrid fuel cell/battery or supercapacitor power sources; 2. Fuel cell multistack power sources; 3. Fuel cell in hybrid power systems for distributed generation. The presented works combine simulation and experimental results.

  2. Mammalian Cell-Based Sensor System

    Science.gov (United States)

    Banerjee, Pratik; Franz, Briana; Bhunia, Arun K.

    Use of living cells or cellular components in biosensors is receiving increased attention and opens a whole new area of functional diagnostics. The term "mammalian cell-based biosensor" is designated to biosensors utilizing mammalian cells as the biorecognition element. Cell-based assays, such as high-throughput screening (HTS) or cytotoxicity testing, have already emerged as dependable and promising approaches to measure the functionality or toxicity of a compound (in case of HTS); or to probe the presence of pathogenic or toxigenic entities in clinical, environmental, or food samples. External stimuli or changes in cellular microenvironment sometimes perturb the "normal" physiological activities of mammalian cells, thus allowing CBBs to screen, monitor, and measure the analyte-induced changes. The advantage of CBBs is that they can report the presence or absence of active components, such as live pathogens or active toxins. In some cases, mammalian cells or plasma membranes are used as electrical capacitors and cell-cell and cell-substrate contact is measured via conductivity or electrical impedance. In addition, cytopathogenicity or cytotoxicity induced by pathogens or toxins resulting in apoptosis or necrosis could be measured via optical devices using fluorescence or luminescence. This chapter focuses mainly on the type and applications of different mammalian cell-based sensor systems.

  3. Cell-based bioassays in microfluidic systems

    Science.gov (United States)

    Itle, Laura J.; Zguris, Jeanna C.; Pishko, Michael V.

    2004-12-01

    The development of cell-based bioassays for high throughput drug screening or the sensing of biotoxins is contingent on the development of whole cell sensors for specific changes in intracellular conditions and the integration of those systems into sample delivery devices. Here we show the feasibility of using a 5-(and-6)-carboxy SNARF-1, acetoxymethyl ester, acetate, a fluorescent dye capable of responding to changes in intracellular pH, as a detection method for the bacterial endotoxin, lipopolysaccharide. We used photolithography to entrap cells with this dye within poly(ethylene) glyocol diacrylate hydrogels in microfluidic channels. After 18 hours of exposure to lipopolysaccharide, we were able to see visible changes in the fluorescent pattern. This work shows the feasibility of using whole cell based biosensors within microfluidic networks to detect cellular changes in response to exogenous agents.

  4. Novel Fuel Cells for Coal Based Systems

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Tao

    2011-12-31

    The goal of this project was to acquire experimental data required to assess the feasibility of a Direct Coal power plant based upon an Electrochemical Looping (ECL) of Liquid Tin Anode Solid Oxide Fuel Cell (LTA-SOFC). The objective of Phase 1 was to experimentally characterize the interaction between the tin anode, coal fuel and cell component electrolyte, the fate of coal contaminants in a molten tin reactor (via chemistry) and their impact upon the YSZ electrolyte (via electrochemistry). The results of this work will provided the basis for further study in Phase 2. The objective of Phase 2 was to extend the study of coal impurities impact on fuel cell components other than electrolyte, more specifically to the anode current collector which is made of an electrically conducting ceramic jacket and broad based coal tin reduction. This work provided a basic proof-of-concept feasibility demonstration of the direct coal concept.

  5. Chip based electroanalytical systems for cell analysis

    DEFF Research Database (Denmark)

    Spegel, C.; Heiskanen, A.; Skjolding, L.H.D.;

    2008-01-01

    This review with 239 references has as its aim to give the reader an introduction to the kinds of methods used for developing microchip based electrode systems as well as to cover the existing literature on electroanalytical systems where microchips play a crucial role for 'nondestructive...

  6. Cell-based microfluidic platform for mimicking human olfactory system.

    Science.gov (United States)

    Lee, Seung Hwan; Oh, Eun Hae; Park, Tai Hyun

    2015-12-15

    Various attempts have been made to mimic the human olfactory system using human olfactory receptors (hORs). In particular, OR-expressed cell-based odorant detection systems mimic the smell sensing mechanism of humans, as they exploit endogenous cellular signaling pathways. However, the majority of such cell-based studies have been performed in the liquid phase to maintain cell viability, and liquid odorants were used as detection targets. Here, we present a microfluidic device for the detection of gaseous odorants which more closely mimics the human olfactory system. Cells expressing hOR were cultured on a porous membrane. The membrane was then flipped over and placed between two compartments. The upper compartment is the gaseous part where gaseous odorants are supplied, while the lower compartment is the aqueous part where viable cells are maintained in the liquid medium. Using this simple microfluidic device, we were able to detect gaseous odorant molecules by a fluorescence signal. The fluorescence signal was generated by calcium influx resulting from the interaction between odorant molecules and the hOR. The system allowed detection of gaseous odorant molecules in real-time, and the findings showed that the fluorescence responses increased dose-dependently in the range of 0-2 ppm odorant. In addition, the system can discriminate among gaseous odorant molecules. This microfluidic system closely mimics the human olfactory system in the sense that the submerged cells detect gaseous odorants.

  7. Model-based fault diagnosis in PEM fuel cell systems

    Energy Technology Data Exchange (ETDEWEB)

    Escobet, T.; de Lira, S.; Puig, V.; Quevedo, J. [Automatic Control Department (ESAII), Universitat Politecnica de Catalunya (UPC), Rambla Sant Nebridi 10, 08222 Terrassa (Spain); Feroldi, D.; Riera, J.; Serra, M. [Institut de Robotica i Informatica Industrial (IRI), Consejo Superior de Investigaciones Cientificas (CSIC), Universitat Politecnica de Catalunya (UPC) Parc Tecnologic de Barcelona, Edifici U, Carrer Llorens i Artigas, 4-6, Planta 2, 08028 Barcelona (Spain)

    2009-07-01

    In this work, a model-based fault diagnosis methodology for PEM fuel cell systems is presented. The methodology is based on computing residuals, indicators that are obtained comparing measured inputs and outputs with analytical relationships, which are obtained by system modelling. The innovation of this methodology is based on the characterization of the relative residual fault sensitivity. To illustrate the results, a non-linear fuel cell simulator proposed in the literature is used, with modifications, to include a set of fault scenarios proposed in this work. Finally, it is presented the diagnosis results corresponding to these fault scenarios. It is remarkable that with this methodology it is possible to diagnose and isolate all the faults in the proposed set in contrast with other well known methodologies which use the binary signature matrix of analytical residuals and faults. (author)

  8. MEMS-based flow cytometry: microfluidics-based cell identification system by fluorescent imaging.

    Science.gov (United States)

    Wu, W K; Liang, C K; Huang, J Z

    2004-01-01

    This study utilizes MEMS technology to realize a novel low-cost microfluidics-based biochip system for flow-type cell handling. Powered by vacuum pump, the microfluidic driving system enables cells to move in order one by one in the biochip by an effect of sheath flow prefocus. Then, cells are guided to a fluorescent inspection region where two detection tasks such as cell image identification and cell counting are conducted. Currently, the glass-based biochip has been manufactured and all the related devices have been well set up in our laboratory. With this proposed prototype system, typical results about cell separation of yeast cell and PC-3 cell are available and their separated images are also presented, respectively. PMID:17270801

  9. SECA Coal-Based Systems - FuelCell Energy, Inc.

    Energy Technology Data Exchange (ETDEWEB)

    Ayagh, Hossein

    2014-01-31

    The overall goal of this U.S. Department of Energy (DOE) sponsored project is the development of solid oxide fuel cell (SOFC) cell and stack technology suitable for use in highly-efficient, economically-competitive central generation power plant facilities fueled by coal synthesis gas (syngas). This program incorporates the following supporting objectives: • Reduce SOFC-based electrical power generation system cost to $700 or less (2007 dollars) for a greater than 100 MW Integrated Gasification Fuel Cell (IGFC) power plant, exclusive of coal gasification and CO2 separation subsystem costs. • Achieve an overall IGFC power plant efficiency of at least 50%, from coal (higher heating value or HHV) to AC power (exclusive of CO2 compression power requirement). • Reduce the release of CO2 to the environment in an IGFC power plant to no more than 10% of the carbon in the syngas. • Increase SOFC stack reliability to achieve a design life of greater than 40,000 hours. At the inception of the project, the efforts were focused on research, design and testing of prototype planar SOFC power generators for stationary applications. FuelCell Energy, Inc. successfully completed the initial stage of the project by meeting the program metrics, culminating in delivery and testing of a 3 kW system at National Energy Technology Laboratory (NETL). Subsequently, the project was re-aligned into a three phase effort with the main goal to develop SOFC technology for application in coal-fueled power plants with >90% carbon capture. Phase I of the Coal-based efforts focused on cell and stack size scale-up with concurrent enhancement of performance, life, cost, and manufacturing characteristics. Also in Phase I, design and analysis of the baseline (greater than 100 MW) power plant system—including concept identification, system definition, and cost analysis—was conducted. Phase II efforts focused on development of a ≥25 kW SOFC stack tower incorporating multiple stack building

  10. SECA Coal-Based Systems - FuelCell Energy, Inc.

    Energy Technology Data Exchange (ETDEWEB)

    Ayagh, Hossein [Fuelcell Energy, Inc., Danbury, CT (United States)

    2014-01-31

    The overall goal of this U.S. Department of Energy (DOE) sponsored project is the development of solid oxide fuel cell (SOFC) cell and stack technology suitable for use in highly-efficient, economically-competitive central generation power plant facilities fueled by coal synthesis gas (syngas). This program incorporates the following supporting objectives: • Reduce SOFC-based electrical power generation system cost to $700 or less (2007 dollars) for a greater than 100 MW Integrated Gasification Fuel Cell (IGFC) power plant, exclusive of coal gasification and CO2 separation subsystem costs. • Achieve an overall IGFC power plant efficiency of at least 50%, from coal (higher heating value or HHV) to AC power (exclusive of CO2 compression power requirement). • Reduce the release of CO2 to the environment in an IGFC power plant to no more than 10% of the carbon in the syngas. • Increase SOFC stack reliability to achieve a design life of greater than 40,000 hours. At the inception of the project, the efforts were focused on research, design and testing of prototype planar SOFC power generators for stationary applications. FuelCell Energy, Inc. successfully completed the initial stage of the project by meeting the program metrics, culminating in delivery and testing of a 3 kW system at National Energy Technology Laboratory (NETL). Subsequently, the project was re-aligned into a three phase effort with the main goal to develop SOFC technology for application in coal-fueled power plants with >90% carbon capture. Phase I of the Coal-based efforts focused on cell and stack size scale-up with concurrent enhancement of performance, life, cost, and manufacturing characteristics. Also in Phase I, design and analysis of the baseline (greater than 100 MW) power plant system—including concept identification, system definition, and cost analysis—was conducted. Phase II efforts focused on development of a ≥25 kW SOFC stack tower incorporating

  11. Modeling and control of fuel cell based distributed generation systems

    Science.gov (United States)

    Jung, Jin Woo

    This dissertation presents circuit models and control algorithms of fuel cell based distributed generation systems (DGS) for two DGS topologies. In the first topology, each DGS unit utilizes a battery in parallel to the fuel cell in a standalone AC power plant and a grid-interconnection. In the second topology, a Z-source converter, which employs both the L and C passive components and shoot-through zero vectors instead of the conventional DC/DC boost power converter in order to step up the DC-link voltage, is adopted for a standalone AC power supply. In Topology 1, two applications are studied: a standalone power generation (Single DGS Unit and Two DGS Units) and a grid-interconnection. First, dynamic model of the fuel cell is given based on electrochemical process. Second, two full-bridge DC to DC converters are adopted and their controllers are designed: an unidirectional full-bridge DC to DC boost converter for the fuel cell and a bidirectional full-bridge DC to DC buck/boost converter for the battery. Third, for a three-phase DC to AC inverter without or with a Delta/Y transformer, a discrete-time state space circuit model is given and two discrete-time feedback controllers are designed: voltage controller in the outer loop and current controller in the inner loop. And last, for load sharing of two DGS units and power flow control of two DGS units or the DGS connected to the grid, real and reactive power controllers are proposed. Particularly, for the grid-connected DGS application, a synchronization issue between an islanding mode and a paralleling mode to the grid is investigated, and two case studies are performed. To demonstrate the proposed circuit models and control strategies, simulation test-beds using Matlab/Simulink are constructed for each configuration of the fuel cell based DGS with a three-phase AC 120 V (L-N)/60 Hz/50 kVA and various simulation results are presented. In Topology 2, this dissertation presents system modeling, modified space

  12. Photoelectrochemical cells based on photosynthetic systems: a review

    Directory of Open Access Journals (Sweden)

    Roman A. Voloshin

    2015-06-01

    Full Text Available Photosynthesis is a process which converts light energy into energy contained in the chemical bonds of organic compounds by photosynthetic pigments such as chlorophyll (Chl a, b, c, d, f or bacteriochlorophyll. It occurs in phototrophic organisms, which include higher plants and many types of photosynthetic bacteria, including cyanobacteria. In the case of the oxygenic photosynthesis, water is a donor of both electrons and protons, and solar radiation serves as inexhaustible source of energy. Efficiency of energy conversion in the primary processes of photosynthesis is close to 100%. Therefore, for many years photosynthesis has attracted the attention of researchers and designers looking for alternative energy systems as one of the most efficient and eco-friendly pathways of energy conversion. The latest advances in the design of optimal solar cells include the creation of converters based on thylakoid membranes, photosystems, and whole cells of cyanobacteria immobilized on nanostructured electrode (gold nanoparticles, carbon nanotubes, nanoparticles of ZnO and TiO2. The mode of solar energy conversion in photosynthesis has a great potential as a source of renewable energy while it is sustainable and environmentally safety as well. Application of pigments such as Chl f and Chl d (unlike Chl a and Chl b, by absorbing the far red and near infrared region of the spectrum (in the range 700-750 nm, will allow to increase the efficiency of such light transforming systems. This review article presents the last achievements in the field of energy photoconverters based on photosynthetic systems.

  13. Research on Software-Cell-Based Software System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The aim of research on software architecture is to improve the quality attributes of software sys tems, such as security, reliability, maintainability, testability , reassembility , evolvability. However, a sin gle running system is hard to achieve all these goals. In this paper, software-cell is introduced as the basic u nit throughout developing process. Then it is further advanced that a robust, safe and high-quality software system is composed of a running system and four supportive systems. This paper especially discusses the structure of software-cell, the construction of the five systems, and the relations between them.

  14. Unique cell culture systems for ground based research

    Science.gov (United States)

    Lewis, Marian L.

    1990-01-01

    The horizontally rotating fluid-filled, membrane oxygenated bioreactors developed at NASA Johnson for spacecraft applications provide a powerful tool for ground-based research. Three-dimensional aggregates formed by cells cultured on microcarrier beads are useful for study of cell-cell interactions and tissue development. By comparing electron micrographs of plant seedlings germinated during Shuttle flight 61-C and in an earth-based rotating bioreactor it is shown that some effects of microgravity are mimicked. Bioreactors used in the UAH Bioreactor Laboratory will make it possible to determine some of the effects of altered gravity at the cellular level. Bioreactors can be valuable for performing critical, preliminary-to-spaceflight experiments as well as medical investigations such as in vitro tumor cell growth and chemotherapeutic drug response; the enrichment of stem cells from bone marrow; and the effect of altered gravity on bone and muscle cell growth and function and immune response depression.

  15. Antioxidant activity of polyphenolic myricetin in vitro cell-free and cell-based systems

    Directory of Open Access Journals (Sweden)

    Abolfazl Barzegar

    2016-06-01

    Full Text Available Myricetin (Myc is one of the most important flavonoids in diet due to its abundance in foods with the highest antioxidant activity. The antioxidant activity of Myc was studied in cell-free and cell-based systems to evaluate the ROS protection efficiency of Myc. The studies were based on the assessment of reducing power of Myc according to ferric ion reduction and intracellular ROS level measurement by assaying the cellular fluorescence intensity using dichlorodihydrofluorescein (DCF probe as an indicator for ROS in cells. Moreover, the antitoxic capability of Myc was assessed using MTT method. Data indicated that intracellular ROS are highly toxic and applying low concentration of Myc not only inhibited cellular ROS production but also was accompanying with the protection of cells against the highly toxic and the lethal effects of peroxide compounds. Because of strong correlation between cellular ROS and their cell toxic properties, the higher antioxidant potency of Myc in cell medium resulted in effectively blocking intracellular ROS and protecting cell death. This property is achieved by the help of high polar solubility and cell membrane permeability of Myc.

  16. Cell Monitoring and Manipulation Systems (CMMSs based on Glass Cell-Culture Chips (GC3s

    Directory of Open Access Journals (Sweden)

    Sebastian M. Buehler

    2016-06-01

    Full Text Available We developed different types of glass cell-culture chips (GC3s for culturing cells for microscopic observation in open media-containing troughs or in microfluidic structures. Platinum sensor and manipulation structures were used to monitor physiological parameters and to allocate and permeabilize cells. Electro-thermal micro pumps distributed chemical compounds in the microfluidic systems. The integrated temperature sensors showed a linear, Pt1000-like behavior. Cell adhesion and proliferation were monitored using interdigitated electrode structures (IDESs. The cell-doubling times of primary murine embryonic neuronal cells (PNCs were determined based on the IDES capacitance-peak shifts. The electrical activity of PNC networks was detected using multi-electrode arrays (MEAs. During seeding, the cells were dielectrophoretically allocated to individual MEAs to improve network structures. MEA pads with diameters of 15, 20, 25, and 35 µm were tested. After 3 weeks, the magnitudes of the determined action potentials were highest for pads of 25 µm in diameter and did not differ when the inter-pad distances were 100 or 170 µm. Using 25-µm diameter circular oxygen electrodes, the signal currents in the cell-culture media were found to range from approximately −0.08 nA (0% O2 to −2.35 nA (21% O2. It was observed that 60-nm thick silicon nitride-sensor layers were stable potentiometric pH sensors under cell-culture conditions for periods of days. Their sensitivity between pH 5 and 9 was as high as 45 mV per pH step. We concluded that sensorized GC3s are potential animal replacement systems for purposes such as toxicity pre-screening. For example, the effect of mefloquine, a medication used to treat malaria, on the electrical activity of neuronal cells was determined in this study using a GC3 system.

  17. Phospholipid polymer-based antibody immobilization for cell rolling surfaces in stem cell purification system.

    Science.gov (United States)

    Mahara, Atsushi; Chen, Hao; Ishihara, Kazuhiko; Yamaoka, Tetsuji

    2014-01-01

    We previously developed an antibody-conjugated cell rolling column that successfully separates stem cell subpopulations depending on the cell surface marker density, but a large amount of the injected cells were retained in the column because of non-specific interactions. In this study, an amphiphilic copolymer, poly[2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate (nBMA)-co-N-vinyl formamide (NVf)], with phospholipid polar side groups was designed as a novel antibody-immobilizing modifier. The formamide groups in NVf units were converted to active maleimide groups. A plastic flow microfluidic chamber was coated with the copolymers, and a reduced anti-CD90 antibody was immobilized. The adipose tissue-derived stem cells isolated from the rat were injected into the flow chamber, and their rolling behavior was observed under a microscope with a high-speed camera. Non-specific cell adhesion was reduced strongly by means of this immobilization method because of the MPC unit, resulting in a high percentage of rolling cells. These results demonstrate that a surface coated with phospholipid polar groups can be used in an effective stem cell separation system based on the cell rolling process.

  18. Multilayer-based lab-on-a-chip systems for perfused cell-based assays

    Science.gov (United States)

    Klotzbach, Udo; Sonntag, Frank; Grünzner, Stefan; Busek, Mathias; Schmieder, Florian; Franke, Volker

    2014-12-01

    A novel integrated technology chain of laser-microstructured multilayer foils for fast, flexible, and low-cost manufacturing of lab-on-a-chip devices especially for complex cell and tissue culture applications, which provides pulsatile fluid flow within physiological ranges at low media-to-cells ratio, was developed and established. Initially the microfluidic system is constructively divided into individual layers, which are formed by separate foils or plates. Based on the functional boundary conditions and the necessary properties of each layer, their corresponding foils and plates are chosen. In the third step, the foils and plates are laser microstructured and functionalized from both sides. In the fourth and last manufacturing step, the multiple plates and foils are joined using different bonding techniques like adhesive bonding, welding, etc. This multilayer technology together with pneumatically driven micropumps and valves permits the manufacturing of fluidic structures and perfusion systems, which spread out above multiple planes. Based on the established lab-on-a-chip platform for perfused cell-based assays, a multilayer microfluidic system with two parallel connected cell culture chambers was successfully implemented.

  19. A cell-based model system links chromothripsis with hyperploidy

    DEFF Research Database (Denmark)

    Mardin, Balca R; Drainas, Alexandros P; Waszak, Sebastian M;

    2015-01-01

    A remarkable observation emerging from recent cancer genome analyses is the identification of chromothripsis as a one-off genomic catastrophe, resulting in massive somatic DNA structural rearrangements (SRs). Largely due to lack of suitable model systems, the mechanistic basis of chromothripsis h...... hyperploid cells. Analysis of primary medulloblastoma cancer genomes verified the link between hyperploidy and chromothripsis in vivo. CAST provides the foundation for mechanistic dissection of complex DNA rearrangement processes....

  20. A Power Allocation Algorithm Based on Cooperative Game Theory in Multi-cell OFDM Systems

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2011-11-01

    Full Text Available A centralized resource allocation algorithm in multi-cell OFDM systems is studied, which aims at improving the performance of wireless communication systems and enhancing user’s spectral efficiency on the edge of the cell. The proposed resource allocation algorithm can be divided into two steps. The first step is sub-carrier allocation based on matrix searching in single cell and the second one is joint power allocation based on cooperative game theory in multi-cell. By comparing with traditional resource allocation algorithms in multi-cell scenario, we find that the proposed algorithm has lower computational complexity and good fairness performance.

  1. MAS-based production scheduling system for manufacturing cell-based workshop

    Institute of Scientific and Technical Information of China (English)

    CHU Hong-yan; CAO Quan-jun; FEI Ren-yuan

    2006-01-01

    The task of production scheduling is to determine the detailed machining path,time,machine tool,etc.,for every work piece,according to the production objective and constraints.It is also an important part of the manufacturing system.In this paper,the manufacturing cell-based workshop is described and its scheduling system structure is established based on MAS (multi-agent system) technology.Through the negotiation and communication of each agent,the machining path is determined and the machining sequence and start time are calculated by GA (genetics algorithm).The communication among agents uses the CORBA (common object request broker architecture) technology of the OMG (Object Management Group).The CORBA-based architecture of the communication is designed and some interfaces for the communication are listed.For the genetics algorithm,chromosome coding,fitness function,parameters selection,and the basic genetics operation including selection,crossover and aberrance,are described.The scheduling system also can deal with some abnormal conditions,such as machine tool failure and urgent tasks.Finally,two scheduling examples are given.

  2. Single-cell-based sensors and synchrotron FTIR spectroscopy: a hybrid system towards bacterial detection.

    Science.gov (United States)

    Veiseh, Mandana; Veiseh, Omid; Martin, Michael C; Bertozzi, Carolyn; Zhang, Miqin

    2007-09-30

    Microarrays of single macrophage cell-based sensors were developed and demonstrated for potential real-time bacterium detection by synchrotron FTIR microscopy. The cells were patterned on gold electrodes of silicon oxide substrates by a surface engineering technique, in which the gold electrodes were immobilized with fibronectin to mediate cell adhesion and the silicon oxide background was passivated with polyethylene glycol (PEG) to resist protein adsorption and cell adhesion. Cell morphology and IR spectra of single, double, and triple cells on gold electrodes exposed to lipopolysaccharide (LPS) of different concentrations were compared to reveal the detection capability of this cell-based sensing platform. The single-cell-based system was found to generate the most significant and consistent IR spectrum shifts upon exposure to LPS, thus providing the highest detection sensitivity. Changes in cell morphology and IR shifts upon cell exposure to LPS were found to be dependent on the LPS concentration and exposure time, which established a method for the identification of LPS concentration and infected cell population. Possibility of using this single-cell system with conventional IR spectroscopy as well as its limitation was investigated by comparing IR spectra of single-cell arrays with gold electrode surface areas of 25, 100, and 400 microm2 using both synchrotron and conventional FTIR spectromicroscopes. This cell-based platform may potentially provide real-time, label-free, and rapid bacterial detection, and allow for high-throughput statistical analyses, and portability. PMID:17560777

  3. Advanced Materials for PEM-Based Fuel Cell Systems

    Energy Technology Data Exchange (ETDEWEB)

    James E. McGrath; Donald G. Baird; Michael von Spakovsky

    2005-10-26

    Proton exchange membrane fuel cells (PEMFCs) are quickly becoming attractive alternative energy sources for transportation, stationary power, and small electronics due to the increasing cost and environmental hazards of traditional fossil fuels. Two main classes of PEMFCs include hydrogen/air or hydrogen/oxygen fuel cells and direct methanol fuel cells (DMFCs). The current benchmark membrane for both types of PEMFCs is Nafion, a perfluorinated sulfonated copolymer made by DuPont. Nafion copolymers exhibit good thermal and chemical stability, as well as very high proton conductivity under hydrated conditions at temperatures below 80 degrees C. However, application of these membranes is limited due to their high methanol permeability and loss of conductivity at high temperatures and low relative humidities. These deficiencies have led to the search for improved materials for proton exchange membranes. Potential PEMs should have good thermal, hydrolytic, and oxidative stability, high proton conductivity, selective permeability, and mechanical durability over long periods of time. Poly(arylene ether)s, polyimides, polybenzimidazoles, and polyphenylenes are among the most widely investigated candidates for PEMs. Poly(arylene ether)s are a promising class of proton exchange membranes due to their excellent thermal and chemical stability and high glass transition temperatures. High proton conductivity can be achieved through post-sulfonation of poly(arylene ether) materials, but this most often results in very high water sorption or even water solubility. Our research has shown that directly polymerized poly(arylene ether) copolymers show important advantages over traditional post-sulfonated systems and also address the concerns with Nafion membranes. These properties were evaluated and correlated with morphology, structure-property relationships, and states of water in the membranes. Further improvements in properties were achieved through incorporation of inorganic

  4. Advanced Materials for PEM-Based Fuel Cell Systems

    Energy Technology Data Exchange (ETDEWEB)

    James E. McGrath

    2005-10-26

    Proton exchange membrane fuel cells (PEMFCs) are quickly becoming attractive alternative energy sources for transportation, stationary power, and small electronics due to the increasing cost and environmental hazards of traditional fossil fuels. Two main classes of PEMFCs include hydrogen/air or hydrogen/oxygen fuel cells and direct methanol fuel cells (DMFCs). The current benchmark membrane for both types of PEMFCs is Nafion, a perfluorinated sulfonated copolymer made by DuPont. Nafion copolymers exhibit good thermal and chemical stability, as well as very high proton conductivity under hydrated conditions at temperatures below 80 °C. However, application of these membranes is limited due to their high methanol permeability and loss of conductivity at high temperatures and low relative humidities. These deficiencies have led to the search for improved materials for proton exchange membranes. Potential PEMs should have good thermal, hydrolytic, and oxidative stability, high proton conductivity, selective permeability, and mechanical durability over long periods of time. Poly(arylene ether)s, polyimides, polybenzimidazoles, and polyphenylenes are among the most widely investigated candidates for PEMs. Poly(arylene ether)s are a promising class of proton exchange membranes due to their excellent thermal and chemical stability and high glass transition temperatures. High proton conductivity can be achieved through post-sulfonation of poly(arylene ether) materials, but this most often results in very high water sorption or even water solubility. Our research has shown that directly polymerized poly(arylene ether) copolymers show important advantages over traditional post-sulfonated systems and also address the concerns with Nafion membranes. These properties were evaluated and correlated with morphology, structure-property relationships, and

  5. A conceptual model of public medical service system based-on cell phone mobile platform

    Science.gov (United States)

    Fu, Hongjiao; Zhao, Yue

    In recent years, cell phones have played an increasingly important role in rapidly-developing global telecommunication services. At present, mobile business develops very fast. However, the development in other mobile service fields, such as public service, mobile medical service, etc, is still in its infant stage. Drawing on the experience of the 'doctor workstation project' which is cooperated by Renmin University of China and Norway Fredskorps Corporation, this paper discusses the research and implementation of the Doctor Workstation System based on cell phone mobile platform. From the practice of the Doctor Workstation System, the paper advances a conceptual model of public medical service system based-on cell phone mobile platform.

  6. A Continuous-Exchange Cell-Free Protein Synthesis System Based on Extracts from Cultured Insect Cells

    OpenAIRE

    Marlitt Stech; Quast, Robert B.; Rita Sachse; Corina Schulze; Wüstenhagen, Doreen A.; Stefan Kubick

    2014-01-01

    In this study, we present a novel technique for the synthesis of complex prokaryotic and eukaryotic proteins by using a continuous-exchange cell-free (CECF) protein synthesis system based on extracts from cultured insect cells. Our approach consists of two basic elements: First, protein synthesis is performed in insect cell lysates which harbor endogenous microsomal vesicles, enabling a translocation of de novo synthesized target proteins into the lumen of the insect vesicles or, in the case ...

  7. Nanog reporter system in mouse embryonic stem cells based on highly efficient BAC homologous recombination

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Nanog is a novel transcription factor specifically expressed in mouse embryonic stem cells (mES cells). It has been reported that Nanog plays an essential role in maintaining multi-potency of ES cells. The expression of Nanog is very sensitive to ES cells differentiation, making Nanog one of the best markers to indicate the status of ES cells. In this study, we developed an efficient method to construct Nanog promoter driven EGFP reporter system based on the BAC homologous recombination. We further generated a Nanog-EGFP reporter mES cell line. This reporter mES cell line exhibited features similar to those of normal mES cells, and the EGFP reporter efficiently reflected the expression of Nanog, indicating the differentiation status of mES cells. We achieved a reliable experimental reporter system to research self-renewal and differentiation of mES cells. The system could facilitate research on culture system of mES cells and researches on the expression and regulation of Nanog and other related factors in mES cells.

  8. Proton exchange membrane fuel cell system diagnosis based on the signed directed graph method

    Science.gov (United States)

    Hua, Jianfeng; Lu, Languang; Ouyang, Minggao; Li, Jianqiu; Xu, Liangfei

    The fuel-cell powered bus is becoming the favored choice for electric vehicles because of its extended driving range, zero emissions, and high energy conversion efficiency when compared with battery-operated electric vehicles. In China, a demonstration program for the fuel cell bus fleet operated at the Beijing Olympics in 2008 and the Shanghai Expo in 2010. It is necessary to develop comprehensive proton exchange membrane fuel cell (PEMFC) diagnostic tools to increase the reliability of these systems. It is especially critical for fuel-cell city buses serving large numbers of passengers using public transportation. This paper presents a diagnostic analysis and implementation study based on the signed directed graph (SDG) method for the fuel-cell system. This diagnostic system was successfully implemented in the fuel-cell bus fleet at the Shanghai Expo in 2010.

  9. Efficient dielectrophoretic cell enrichment using a dielectrophoresis-well based system.

    Science.gov (United States)

    Abdul Razak, Mohd Azhar; Hoettges, Kai F; Fatoyinbo, Henry O; Labeed, Fatima H; Hughes, Michael P

    2013-01-01

    Whilst laboratory-on-chip cell separation systems using dielectrophoresis are increasingly reported in the literature, many systems are afflicted by factors which impede "real world" performance, chief among these being cell loss (in dead spaces, attached to glass and tubing surfaces, or sedimentation from flow), and designs with large channel height-to-width ratios (large channel widths, small channel heights) that make the systems difficult to interface with other microfluidic systems. In this paper, we present a scalable structure based on 3D wells with approximately unity height-to-width ratios (based on tubes with electrodes on the sides), which is capable of enriching yeast cell populations whilst ensuring that up to 94.3% of cells processed through the device can be collected in tubes beyond the output.

  10. Vision-based Nano Robotic System for High-throughput Non-embedded Cell Cutting

    Science.gov (United States)

    Shang, Wanfeng; Lu, Haojian; Wan, Wenfeng; Fukuda, Toshio; Shen, Yajing

    2016-03-01

    Cell cutting is a significant task in biology study, but the highly productive non-embedded cell cutting is still a big challenge for current techniques. This paper proposes a vision-based nano robotic system and then realizes automatic non-embedded cell cutting with this system. First, the nano robotic system is developed and integrated with a nanoknife inside an environmental scanning electron microscopy (ESEM). Then, the positions of the nanoknife and the single cell are recognized, and the distance between them is calculated dynamically based on image processing. To guarantee the positioning accuracy and the working efficiency, we propose a distance-regulated speed adapting strategy, in which the moving speed is adjusted intelligently based on the distance between the nanoknife and the target cell. The results indicate that the automatic non-embedded cutting is able to be achieved within 1–2 mins with low invasion benefiting from the high precise nanorobot system and the sharp edge of nanoknife. This research paves a way for the high-throughput cell cutting at cell’s natural condition, which is expected to make significant impact on the biology studies, especially for the in-situ analysis at cellular and subcellular scale, such as cell interaction investigation, neural signal transduction and low invasive cell surgery.

  11. Microfluidic biosensing systems based on enzymes, antibodies and cells

    OpenAIRE

    Davidsson, Richard

    2004-01-01

    The rapid developments within the life science and biotechnology areas put up ever-new demands on more sophisticated techniques and methods for chemical and biological analysis to reach deeper insight into the events at molecular level. Miniaturisation of assays and systems on microchips is one way to increase throughput and advance through parallel analysis lines, multiplexing and integration. This thesis shows some aspects on the use of silicon microchips as a platform for immobilisation of...

  12. Characterisation of a hybrid, fuel-cell-based propulsion system for small unmanned aircraft

    Science.gov (United States)

    Verstraete, D.; Lehmkuehler, K.; Gong, A.; Harvey, J. R.; Brian, G.; Palmer, J. L.

    2014-03-01

    Advanced hybrid powerplants combining a fuel cell and battery can enable significantly higher endurance for small, electrically powered unmanned aircraft systems, compared with batteries alone. However, detailed investigations of the static and dynamic performance of such systems are required to address integration challenges. This article describes a series of tests used to characterise the Horizon Energy Systems' AeroStack hybrid, fuel-cell-based powertrain. The results demonstrate that a significant difference can exist between the dynamic performance of the fuel-cell system and its static polarisation curve, confirming the need for detailed measurements. The results also confirm that the AeroStack's lithium-polymer battery plays a crucial role in its response to dynamic load changes and protects the fuel cell from membrane dehydration and fuel starvation. At low static loads, the AeroStack fuel cell recharges the battery with currents up to 1 A, which leads to further differences with the polarisation curve.

  13. Optimization and Evaluation of a Novel Size Based Circulating Tumor Cell Isolation System.

    Directory of Open Access Journals (Sweden)

    Lei Xu

    Full Text Available Isolation of circulating tumor cells (CTCs from peripheral blood has the potential to provide a far easier "liquid biopsy" than tumor tissue biopsies, to monitor tumor cell populations during disease progression and in response to therapies. Many CTC isolation technologies have been developed. We optimized the Parsortix system, an epitope independent, size and compressibility-based platform for CTCs isolation, making it possible to harvest CTCs at the speed and sample volume comparable to standard CellSearch system. We captured more than half of cancer cells from different cancer cell lines spiked in blood samples from healthy donors using this system. Cell loss during immunostaining of cells transferred and fixed on the slides is a major problem for analyzing rare cell samples. We developed a novel cell transfer and fixation method to retain >90% of cells on the slide after the immunofluorescence process without affecting signal strength and specificity. Using this optimized method, we evaluated the Parsortix system for CTC harvest in prostate cancer patients in comparison to immunobead based CTC isolation systems IsoFlux and CellSearch. We harvested a similar number (p = 0.33 of cytokeratin (CK positive CTCs using Parsortix and IsoFlux from 7.5 mL blood samples of 10 prostate cancer patients (an average of 33.8 and 37.6 respectively. The purity of the CTCs harvested by Parsortix at 3.1% was significantly higher than IsoFlux at 1.0% (p = 0.02. Parsortix harvested significantly more CK positive CTCs than CellSearch (p = 0.04 in seven prostate cancer patient samples, where both systems were utilized (an average of 32.1 and 10.1 respectively. We also captured CTC clusters using Parsortix. Using four-color immunofluorescence we found that 85.8% of PC3 cells expressed EpCAM, 91.7% expressed CK and 2.5% cells lacked both epithelial markers. Interestingly, 95.6% of PC3 cells expressed Vimentin, including those cells that lacked both epithelial marker

  14. Optimization and Evaluation of a Novel Size Based Circulating Tumor Cell Isolation System.

    Science.gov (United States)

    Xu, Lei; Mao, Xueying; Imrali, Ahmet; Syed, Ferrial; Mutsvangwa, Katherine; Berney, Daniel; Cathcart, Paul; Hines, John; Shamash, Jonathan; Lu, Yong-Jie

    2015-01-01

    Isolation of circulating tumor cells (CTCs) from peripheral blood has the potential to provide a far easier "liquid biopsy" than tumor tissue biopsies, to monitor tumor cell populations during disease progression and in response to therapies. Many CTC isolation technologies have been developed. We optimized the Parsortix system, an epitope independent, size and compressibility-based platform for CTCs isolation, making it possible to harvest CTCs at the speed and sample volume comparable to standard CellSearch system. We captured more than half of cancer cells from different cancer cell lines spiked in blood samples from healthy donors using this system. Cell loss during immunostaining of cells transferred and fixed on the slides is a major problem for analyzing rare cell samples. We developed a novel cell transfer and fixation method to retain >90% of cells on the slide after the immunofluorescence process without affecting signal strength and specificity. Using this optimized method, we evaluated the Parsortix system for CTC harvest in prostate cancer patients in comparison to immunobead based CTC isolation systems IsoFlux and CellSearch. We harvested a similar number (p = 0.33) of cytokeratin (CK) positive CTCs using Parsortix and IsoFlux from 7.5 mL blood samples of 10 prostate cancer patients (an average of 33.8 and 37.6 respectively). The purity of the CTCs harvested by Parsortix at 3.1% was significantly higher than IsoFlux at 1.0% (p = 0.02). Parsortix harvested significantly more CK positive CTCs than CellSearch (p = 0.04) in seven prostate cancer patient samples, where both systems were utilized (an average of 32.1 and 10.1 respectively). We also captured CTC clusters using Parsortix. Using four-color immunofluorescence we found that 85.8% of PC3 cells expressed EpCAM, 91.7% expressed CK and 2.5% cells lacked both epithelial markers. Interestingly, 95.6% of PC3 cells expressed Vimentin, including those cells that lacked both epithelial marker expression

  15. Cell Based Drug Delivery System through Resealed Erythrocyte - A Review

    Directory of Open Access Journals (Sweden)

    A Gupta

    2010-01-01

    Full Text Available Erythrocytes are biocompatible, biodegradable, possess long circulation half lives, and can be loaded with a variety of biologically active compounds using various chemical and physical methods. Erythrocytes are potential biocompatible vectors for different bioactive substances, including drugs. These can be used successfully as biological carriers of drugs, enzymes and peptides. There are currently diverse methods that permit drug encapsulation in erythrocytes with an appropriate yield. Erythrocytes loaded with drugs and other substances allow for different release rates to be obtained. Encapsulation in erythrocytes significantly changes the pharmacokinetic properties of drugs in both animals and humans, enhancing liver and spleen uptake and targeting the reticulo-endothelial system (RES. This review explains the different method of drug loading and their characterization parameters for resealed erythrocytes. This method of drug targeting is safe and effective for longer period of time and beneficial for the society.

  16. Metabolic response of lung cancer cells to radiation in a paper-based 3D cell culture system.

    Science.gov (United States)

    Simon, Karen A; Mosadegh, Bobak; Minn, Kyaw Thu; Lockett, Matthew R; Mohammady, Marym R; Boucher, Diane M; Hall, Amy B; Hillier, Shawn M; Udagawa, Taturo; Eustace, Brenda K; Whitesides, George M

    2016-07-01

    This work demonstrates the application of a 3D culture system-Cells-in-Gels-in-Paper (CiGiP)-in evaluating the metabolic response of lung cancer cells to ionizing radiation. The 3D tissue-like construct-prepared by stacking multiple sheets of paper containing cell-embedded hydrogels-generates a gradient of oxygen and nutrients that decreases monotonically in the stack. Separating the layers of the stack after exposure enabled analysis of the cellular response to radiation as a function of oxygen and nutrient availability; this availability is dictated by the distance between the cells and the source of oxygenated medium. As the distance between the cells and source of oxygenated media increased, cells show increased levels of hypoxia-inducible factor 1-alpha, decreased proliferation, and reduced sensitivity to ionizing radiation. Each of these cellular responses are characteristic of cancer cells observed in solid tumors. With this setup we were able to differentiate three isogenic variants of A549 cells based on their metabolic radiosensitivity; these three variants have known differences in their metastatic behavior in vivo. This system can, therefore, capture some aspects of radiosensitivity of populations of cancer cells related to mass-transport phenomenon, carry out systematic studies of radiation response in vitro that decouple effects from migration and proliferation of cells, and regulate the exposure of oxygen to subpopulations of cells in a tissue-like construct either before or after irradiation. PMID:27116031

  17. Subcarrier and power allocation algorithm based on inter-cell interference mitigation for OFDMA system

    Institute of Scientific and Technical Information of China (English)

    ZOU Ting; DENG Gang; WANG Ying; ZHANG Ping

    2007-01-01

    This article proposes a dynamic subcarrier and power allocation algorithm for multicell orthogonal frequency division multiple access (OFDMA) downlink system, based on inter-cell interference (ICI) mitigation. Different from other ICI mitigation schemes, which pay little attention to power allocation in the system, the proposed algorithm assigns channels to each user, based on proportional-fair (PF) scheduling and ICI coordination, whereas allocating power is based on link gain distribution and the loading bit based on adaptive modulation and coding (AMC) in base transceiver station (BTS). Simulation results show that the algorithm yields better performance for data services under fast fading.

  18. Developing a microfluidic-based system to quantify cell capture efficiency

    Institute of Scientific and Technical Information of China (English)

    YANG Fan; GAO YuXin; ZHANG Yan; CHEN Juan; LONG Mian

    2009-01-01

    Micro-fabrication technology has substantial potential for identifying molecular markers expressed on the surfaces of tissue cells and viruses. It has been found in several conceptual prototypes that cells with such markers are able to be captured by their antibodies immobilized on microchannel substrates and unbound cells are flushed out by a driven flow. The feasibility and reliability of such a microfluidic-based assay, however, remains to be further tested. In the current work, we developed a microflu-idic-based system consisting of a microfluidic chip, an image grabbing unit, data acquisition and analysis software, as well as a supporting base. Specific binding of CD59-expressed or BSA-coupled human red blood cells (RBCs) to anti-CD59 or anti-BSA antibody-immobilized chip surfaces was quan-tiffed by capture efficiency and by the fraction of bound cells. Impacts of respective flow rate, cell concentration, antibody concentration and site density were tested systematically. The measured data indicated that the assay was robust. The robustness was further confirmed by capture efficiencies measured from an independent EUSA-based cell binding assay. These results demonstrated that the system developed provided a new plallorm to effectively quantify cellular surface markers effectively, which promoted the potential applications in both biological studies and clinical diagnoses.

  19. Developing a microfluidic-based system to quantify cell capture efficiency

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Micro-fabrication technology has substantial potential for identifying molecular markers expressed on the surfaces of tissue cells and viruses. It has been found in several conceptual prototypes that cells with such markers are able to be captured by their antibodies immobilized on microchannel substrates and unbound cells are flushed out by a driven flow. The feasibility and reliability of such a microflu- idic-based assay, however, remains to be further tested. In the current work, we developed a microflu- idic-based system consisting of a microfluidic chip, an image grabbing unit, data acquisition and analysis software, as well as a supporting base. Specific binding of CD59-expressed or BSA-coupled human red blood cells (RBCs) to anti-CD59 or anti-BSA antibody-immobilized chip surfaces was quan- tified by capture efficiency and by the fraction of bound cells. Impacts of respective flow rate, cell concentration, antibody concentration and site density were tested systematically. The measured data indicated that the assay was robust. The robustness was further confirmed by capture efficiencies measured from an independent ELISA-based cell binding assay. These results demonstrated that the system developed provided a new platform to effectively quantify cellular surface markers effectively, which promoted the potential applications in both biological studies and clinical diagnoses.

  20. Optimization and Evaluation of a Novel Size Based Circulating Tumor Cell Isolation System

    OpenAIRE

    Lei Xu; Xueying Mao; Ahmet Imrali; Ferrial Syed; Katherine Mutsvangwa; Daniel Berney; Paul Cathcart; John Hines; Jonathan Shamash; Yong-Jie Lu

    2015-01-01

    Isolation of circulating tumor cells (CTCs) from peripheral blood has the potential to provide a far easier "liquid biopsy" than tumor tissue biopsies, to monitor tumor cell populations during disease progression and in response to therapies. Many CTC isolation technologies have been developed. We optimized the Parsortix system, an epitope independent, size and compressibility-based platform for CTCs isolation, making it possible to harvest CTCs at the speed and sample volume comparable to st...

  1. A Versatile System for USER Cloning-Based Assembly of Expression Vectors for Mammalian Cell Engineering

    DEFF Research Database (Denmark)

    Lund, Anne Mathilde; Kildegaard, Helene Faustrup; Petersen, Maja Borup Kjær;

    2014-01-01

    A new versatile mammalian vector system for protein production, cell biology analyses, and cell factory engineering was developed. The vector system applies the ligation-free uracil-excision based technique – USER cloning – to rapidly construct mammalian expression vectors of multiple DNA fragments...... efficiency above 90%. The functionality of basic vectors for FAST assembly was tested and validated by transient expression of fluorescent model proteins in CHO, U-2-OS and HEK293 cell lines. In this test, we included many of the most common vector elements for heterologous gene expression in mammalian cells...... and with maximum flexibility, both for choice of vector backbone and cargo. The vector system includes a set of basic vectors and a toolbox containing a multitude of DNA building blocks including promoters, terminators, selectable marker- and reporter genes, and sequences encoding an internal ribosome entry site...

  2. Optimization of cell line development in the GS-CHO expression system using a high-throughput, single cell-based clone selection system.

    Science.gov (United States)

    Nakamura, Tsuyoshi; Omasa, Takeshi

    2015-09-01

    Therapeutic antibodies are commonly produced by high-expressing, clonal and recombinant Chinese hamster ovary (CHO) cell lines. Currently, CHO cells dominate as a commercial production host because of their ease of use, established regulatory track record, and safety profile. CHO-K1SV is a suspension, protein-free-adapted CHO-K1-derived cell line employing the glutamine synthetase (GS) gene expression system (GS-CHO expression system). The selection of high-producing mammalian cell lines is a crucial step in process development for the production of therapeutic antibodies. In general, cloning by the limiting dilution method is used to isolate high-producing monoclonal CHO cells. However, the limiting dilution method is time consuming and has a low probability of monoclonality. To minimize the duration and increase the probability of obtaining high-producing clones with high monoclonality, an automated single cell-based clone selector, the ClonePix FL system, is available. In this study, we applied the high-throughput ClonePix FL system for cell line development using CHO-K1SV cells and investigated efficient conditions for single cell-based clone selection. CHO-K1SV cell growth at the pre-picking stage was improved by optimizing the formulation of semi-solid medium. The efficiency of picking and cell growth at the post-picking stage was improved by optimization of the plating time without decreasing the diversity of clones. The conditions for selection, including the medium formulation, were the most important factors for the single cell-based clone selection system to construct a high-producing CHO cell line. PMID:25792187

  3. Evaluation of a content-based retrieval system for blood cell images with automated methods.

    Science.gov (United States)

    Seng, Woo Chaw; Mirisaee, Seyed Hadi

    2011-08-01

    Content-based image retrieval techniques have been extensively studied for the past few years. With the growth of digital medical image databases, the demand for content-based analysis and retrieval tools has been increasing remarkably. Blood cell image is a key diagnostic tool for hematologists. An automated system that can retrieved relevant blood cell images correctly and efficiently would save the effort and time of hematologists. The purpose of this work is to develop such a content-based image retrieval system. Global color histogram and wavelet-based methods are used in the prototype. The system allows users to search by providing a query image and select one of four implemented methods. The obtained results demonstrate the proposed extended query refinement has the potential to capture a user's high level query and perception subjectivity by dynamically giving better query combinations. Color-based methods performed better than wavelet-based methods with regard to precision, recall rate and retrieval time. Shape and density of blood cells are suggested as measurements for future improvement. The system developed is useful for undergraduate education. PMID:20703533

  4. Development of an energy consumption and cost data base for fuel cell total energy systems and conventional building energy systems

    Science.gov (United States)

    Pine, G. D.; Christian, J. E.; Mixon, W. R.; Jackson, W. L.

    1980-07-01

    The procedures and data sources used to develop an energy consumption and system cost data base for use in predicting the market penetration of phosphoric acid fuel cell total energy systems in the nonindustrial building market are described. A computer program was used to simulate the hourly energy requirements of six types of buildings; office buildings; retail stores; hotels and motels; schools; hospitals; and multifamily residences. The simulations were done by using hourly weather tapes for one city in each of the ten Department of Energy administrative regions. Two types of building construction were considered, one for existing buildings and one for new buildings. A fuel cell system combined with electrically driven heat pumps and one combined with a gas boiler and an electrically driven chiller were compared with similar conventional systems. The methods of system simulation, component sizing, and system cost estimation are described for each system.

  5. Modeling of a 5-cell direct methanol fuel cell using adaptive-network-based fuzzy inference systems

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Rongrong; Li, Chunwen [Department of Automation, Tsinghua University, Beijing 100084 (China); Qi, Liang; Xie, Xiaofeng [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Ding, Qingqing [Department of Electrical Engineering, Tsinghua University, Beijing 100084 (China); Ma, ChenChi M. [National Tsing Hua University, Hsinchu 300 (China)

    2008-12-01

    The methanol concentrations, temperature and current were considered as inputs, the cell voltage was taken as output, and the performance of a direct methanol fuel cell (DMFC) was modeled by adaptive-network-based fuzzy inference systems (ANFIS). The artificial neural network (ANN) and polynomial-based models were selected to be compared with the ANFIS in respect of quality and accuracy. Based on the ANFIS model obtained, the characteristics of the DMFC were studied. The results show that temperature and methanol concentration greatly affect the performance of the DMFC. Within a restricted current range, the methanol concentration does not greatly affect the stack voltage. In order to obtain higher fuel utilization efficiency, the methanol concentrations and temperatures should be adjusted according to the load on the system. (author)

  6. Automated cervical precancerous cells screening system based on Fourier transform infrared spectroscopy features

    Science.gov (United States)

    Jusman, Yessi; Mat Isa, Nor Ashidi; Ng, Siew-Cheok; Hasikin, Khairunnisa; Abu Osman, Noor Azuan

    2016-07-01

    Fourier transform infrared (FTIR) spectroscopy technique can detect the abnormality of a cervical cell that occurs before the morphological change could be observed under the light microscope as employed in conventional techniques. This paper presents developed features extraction for an automated screening system for cervical precancerous cell based on the FTIR spectroscopy as a second opinion to pathologists. The automated system generally consists of the developed features extraction and classification stages. Signal processing techniques are used in the features extraction stage. Then, discriminant analysis and principal component analysis are employed to select dominant features for the classification process. The datasets of the cervical precancerous cells obtained from the feature selection process are classified using a hybrid multilayered perceptron network. The proposed system achieved 92% accuracy.

  7. Virtual reality based support system for layout planning and programming of an industrial robotic work cell.

    Science.gov (United States)

    Yap, Hwa Jen; Taha, Zahari; Dawal, Siti Zawiah Md; Chang, Siow-Wee

    2014-01-01

    Traditional robotic work cell design and programming are considered inefficient and outdated in current industrial and market demands. In this research, virtual reality (VR) technology is used to improve human-robot interface, whereby complicated commands or programming knowledge is not required. The proposed solution, known as VR-based Programming of a Robotic Work Cell (VR-Rocell), consists of two sub-programmes, which are VR-Robotic Work Cell Layout (VR-RoWL) and VR-based Robot Teaching System (VR-RoT). VR-RoWL is developed to assign the layout design for an industrial robotic work cell, whereby VR-RoT is developed to overcome safety issues and lack of trained personnel in robot programming. Simple and user-friendly interfaces are designed for inexperienced users to generate robot commands without damaging the robot or interrupting the production line. The user is able to attempt numerous times to attain an optimum solution. A case study is conducted in the Robotics Laboratory to assemble an electronics casing and it is found that the output models are compatible with commercial software without loss of information. Furthermore, the generated KUKA commands are workable when loaded into a commercial simulator. The operation of the actual robotic work cell shows that the errors may be due to the dynamics of the KUKA robot rather than the accuracy of the generated programme. Therefore, it is concluded that the virtual reality based solution approach can be implemented in an industrial robotic work cell.

  8. Study on Cell Error Rate of a Satellite ATM System Based on CDMA

    Institute of Scientific and Technical Information of China (English)

    赵彤宇; 张乃通

    2003-01-01

    In this paper, the cell error rate (CER) of a CDMA-based satellite ATM system is analyzed. Two fading models, i.e. the partial fading model and the total fading model are presented according to multi-path propagation fading and shadow effect. Based on the total shadow model, the relation of CER vs. the number of subscribers at various elevations under 2D-RAKE receiving and non-diversity receiving is got. The impact on cell error rate with pseudo noise (PN) code length is also considered. The result that the maximum likelihood combination of multi-path signal would not improve the system performance when multiple access interference (MAI) is small, on the contrary the performance may be even worse is abtained.

  9. First experience with particle-in-cell plasma physics code on ARM-based HPC systems

    Science.gov (United States)

    Sáez, Xavier; Soba, Alejandro; Sánchez, Edilberto; Mantsinen, Mervi; Mateo, Sergi; Cela, José M.; Castejón, Francisco

    2015-09-01

    In this work, we will explore the feasibility of porting a Particle-in-cell code (EUTERPE) to an ARM multi-core platform from the Mont-Blanc project. The used prototype is based on a system-on-chip Samsung Exynos 5 with an integrated GPU. It is the first prototype that could be used for High-Performance Computing (HPC), since it supports double precision and parallel programming languages.

  10. An efficient strategy for cell-based antibody library selection using an integrated vector system

    Directory of Open Access Journals (Sweden)

    Yoon Hyerim

    2012-09-01

    Full Text Available Abstract Background Cell panning of phage-displayed antibody library is a powerful tool for the development of therapeutic and imaging agents since disease-related cell surface proteins in native complex conformation can be directly targeted. Here, we employed a strategy taking advantage of an integrated vector system which allows rapid conversion of scFv-displaying phage into scFv-Fc format for efficient cell-based scFv library selection on a tetraspanin protein, CD9. Results A mouse scFv library constructed by using a phagemid vector, pDR-D1 was subjected to cell panning against stable CD9 transfectant, and the scFv repertoire from the enriched phage pool was directly transferred to a mammalian cassette vector, pDR-OriP-Fc1. The resulting constructs enabled transient expression of enough amounts of scFv-Fcs in HEK293E cells, and flow cytometric screening of binders for CD9 transfectant could be performed simply by using the culture supernatants. All three clones selected from the screening showed correct CD9-specificity. They could immunoprecipitate CD9 molecules out of the transfectant cell lysate and correctly stain endogenous CD9 expression on cancer cell membrane. Furthermore, competition assay with a known anti-CD9 monoclonal antibody (mAb suggested that the binding epitopes of some of them overlap with that of the mAb which resides within the large extracellular loop of CD9. Conclusions This study demonstrates that scFv-Fc from mammalian transient expression can be chosen as a reliable format for rapid screening and validation in cell-based scFv library selection, and the strategy described here will be applicable to efficient discovery of antibodies to diverse cell-surface targets.

  11. A versatile system for USER cloning-based assembly of expression vectors for mammalian cell engineering.

    Directory of Open Access Journals (Sweden)

    Anne Mathilde Lund

    Full Text Available A new versatile mammalian vector system for protein production, cell biology analyses, and cell factory engineering was developed. The vector system applies the ligation-free uracil-excision based technique--USER cloning--to rapidly construct mammalian expression vectors of multiple DNA fragments and with maximum flexibility, both for choice of vector backbone and cargo. The vector system includes a set of basic vectors and a toolbox containing a multitude of DNA building blocks including promoters, terminators, selectable marker- and reporter genes, and sequences encoding an internal ribosome entry site, cellular localization signals and epitope- and purification tags. Building blocks in the toolbox can be easily combined as they contain defined and tested Flexible Assembly Sequence Tags, FASTs. USER cloning with FASTs allows rapid swaps of gene, promoter or selection marker in existing plasmids and simple construction of vectors encoding proteins, which are fused to fluorescence-, purification-, localization-, or epitope tags. The mammalian expression vector assembly platform currently allows for the assembly of up to seven fragments in a single cloning step with correct directionality and with a cloning efficiency above 90%. The functionality of basic vectors for FAST assembly was tested and validated by transient expression of fluorescent model proteins in CHO, U-2-OS and HEK293 cell lines. In this test, we included many of the most common vector elements for heterologous gene expression in mammalian cells, in addition the system is fully extendable by other users. The vector system is designed to facilitate high-throughput genome-scale studies of mammalian cells, such as the newly sequenced CHO cell lines, through the ability to rapidly generate high-fidelity assembly of customizable gene expression vectors.

  12. A Fluid Membrane-Based Soluble Ligand Display System for Live CellAssays

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Jwa-Min; Nair, Pradeep N.; Neve, Richard M.; Gray, Joe W.; Groves, Jay T.

    2005-10-14

    Cell communication modulates numerous biological processes including proliferation, apoptosis, motility, invasion and differentiation. Correspondingly, there has been significant interest in the development of surface display strategies for the presentation of signaling molecules to living cells. This effort has primarily focused on naturally surface-bound ligands, such as extracellular matrix components and cell membranes. Soluble ligands (e.g. growth factors and cytokines) play an important role in intercellular communications, and their display in a surface-bound format would be of great utility in the design of array-based live cell assays. Recently, several cell microarray systems that display cDNA, RNAi, or small molecules in a surface array format were proven to be useful in accelerating high-throughput functional genetic studies and screening therapeutic agents. These surface display methods provide a flexible platform for the systematic, combinatorial investigation of genes and small molecules affecting cellular processes and phenotypes of interest. In an analogous sense, it would be an important advance if one could display soluble signaling ligands in a surface assay format that allows for systematic, patterned presentation of soluble ligands to live cells. Such a technique would make it possible to examine cellular phenotypes of interest in a parallel format with soluble signaling ligands as one of the display parameters. Herein we report a ligand-modified fluid supported lipid bilayer (SLB) assay system that can be used to functionally display soluble ligands to cells in situ (Figure 1A). By displaying soluble ligands on a SLB surface, both solution behavior (the ability to become locally enriched by reaction-diffusion processes) and solid behavior (the ability to control the spatial location of the ligands in an open system) could be combined. The method reported herein benefits from the naturally fluid state of the supported membrane, which allows

  13. Solar cells based on the poly(N-vinylcarbazole):porphyrin:tris(8-hydroxyquinolinato) aluminium blend system

    Institute of Scientific and Technical Information of China (English)

    Zhang Tian-Hui; Zhao Su-Ling; Piao Ling-Yu; Xu Zheng; Ju Si-Ting; Liu Xiao-Dong; Kong Chao; Xu Xu-Rong

    2011-01-01

    Organic solar cells based on poly(N-vinylcarbazole) (PVK): porphyrin: tris (8-hydroxyquinolinato) aluminium (Alq3) blend p-n junction systems have been fabricated in this work. The roles of the different components in the blend system and of the amount of porphyrin have been investigated. The 5, 10, 15, 20-tetraphenylporphyrin (TPP) and 5, 10, 15, 20-tetra(o-chloro)phenylporphyrinato-copper (CuTCIPP) are used in the solar cells. The results show that TPP is better than CuTClPP in enhancing the performance of PVK:Alq3 solar cells. When the weight ratio of PVK:TPP:Alq3 is 1:1.5:1, the best performance of solar cell is obtained. The open circuit voltage (Voc) is 0.87 V, and the short circuit current (Jsc) is 17.5 μA·cm-2. In the ternary bulk hereojunction system, the device may be regarded as a cascade of three devices of PVK:TPP, TPP:Alq3 and PVK:Alq3. PVK, TPP and Alq3 can improve the hole mobility, light absorption intensity and electron mobility of the ternary bulk hereojunction system, respectively.

  14. Residential Systems Based on Solid Oxide Fuel Cells for Scandinavian Climate

    DEFF Research Database (Denmark)

    Rokni, Masoud; Vialetto, Giulio

    2015-01-01

    Energy saving is an open point in most European countries where energy policies are oriented to reduce the use of fossil fuels, greenhouses emissions and energy independence and to increase the use of renewable energies. In the last several years, new technologies have been developed, and some...... of them received subsidies to increase installation and reduce cost. This article presents an innovative cogeneration system based on a solid oxide fuel cell (SOFC) system and heat pump for household applications with a focus on primary energy and economic savings using electric equivalent load parameter...

  15. A cell-based screening system for anti-influenza A virus agents

    Science.gov (United States)

    Wong, Wan Ying; Loh, Sheng Wei; Ng, Wei Lun; Tan, Ming Cheang; Yeo, Kok Siong; Looi, Chung Yeng; Maah, Mohd Jamil; Ea, Chee-Kwee

    2015-01-01

    Emerging of drug resistant influenza A virus (IAV) has been a big challenge for anti-IAV therapy. In this study, we describe a relatively easy and safe cell-based screening system for anti-IAV replication inhibitors using a non-replicative strain of IAV. A nickel (II) complex of polyhydroxybenzaldehyde N4-thiosemicarbazone (NiPT5) was recently found to exhibit anti-inflammatory activity in vivo and in vitro. NiPT5 impedes the signaling cascades that lead to the activation of NF-κB in response to different stimuli, such as LPS and TNFα. Using our cell-based screening system, we report that pretreating cells with NiPT5 protects cells from influenza A virus (IAV) and vesicular stomatitis virus (VSV) infection. Furthermore, NiPT5 inhibits replication of IAV by inhibiting transcription and translation of vRNAs of IAV. Additionally, NiPT5 reduces IAV-induced type I interferon response and cytokines production. Moreover, NiPT5 prevents activation of NF-κB, and IRF3 in response to IAV infection. These results demonstrate that NiPT5 is a potent antiviral agent that inhibits the early phase of IAV replication. PMID:25728279

  16. Advanced control approach for hybrid systems based on solid oxide fuel cells

    International Nuclear Information System (INIS)

    Highlights: • Advanced new control system for SOFC based hybrid plants. • Proportional–Integral approach with feed-forward technology. • Good control of fuel cell temperature. • All critical properties maintained inside safe conditions. - Abstract: This paper shows a new advanced control approach for operations in hybrid systems equipped with solid oxide fuel cell technology. This new tool, which combines feed-forward and standard proportional–integral techniques, controls the system during load changes avoiding failures and stress conditions detrimental to component life. This approach was selected to combine simplicity and good control performance. Moreover, the new approach presented in this paper eliminates the need for mass flow rate meters and other expensive probes, as usually required for a commercial plant. Compared to previous works, better performance is achieved in controlling fuel cell temperature (maximum gradient significantly lower than 3 K/min), reducing the pressure gap between cathode and anode sides (at least a 30% decrease during transient operations), and generating a higher safe margin (at least a 10% increase) for the Steam-to-Carbon Ratio. This new control system was developed and optimized using a hybrid system transient model implemented, validated and tested within previous works. The plant, comprising the coupling of a tubular solid oxide fuel cell stack with a microturbine, is equipped with a bypass valve able to connect the compressor outlet with the turbine inlet duct for rotational speed control. Following model development and tuning activities, several operative conditions were considered to show the new control system increased performance compared to previous tools (the same hybrid system model was used with the new control approach). Special attention was devoted to electrical load steps and ramps considering significant changes in ambient conditions

  17. Expression System Based on an MTIIa Promoter to Produce hPSA in Mammalian Cell Cultures.

    Science.gov (United States)

    Santos, Anderson K; Parreira, Ricardo C; Resende, Rodrigo R

    2016-01-01

    Because of the limitations of standard culture techniques, the development of new recombinant protein expression systems with biotechnological potential is a key challenge. Ideally, such systems should be able to effectively and accurately synthesize a protein of interest with intrinsic metabolic capacity. Here, we describe such a system that was designed based on a plasmid vector containing promoter elements derived from the metallothionein MTIIa promoter, as well as processing and purification elements. This promoter can be induced by heavy metals in a culture medium to induce the synthesis of human prostate-specific antigen (hPSA), which has been modified to insert elements for purification, proteolysis, and secretion. We optimized hPSA production in this system by comparing the effects and contributions of ZnCl2, CdCl2, and CuSO4 in HEK293FT, HeLa, BHK-21, and CHO-K1 cells. We also compared the effectiveness of three different transfection agents: multi-walled carbon nanotubes, Lipofectamine 2000, and X-tremeGENE HP Reagent. hPSA production was confirmed via the detection of enhanced green fluorescent protein fluorescence, and cell viability was determined. The expression of hPSA was compared with that of the native protein produced by LNCaP cells, using enzyme-linked immunosorbent assay and sodium dodecyl sulfate polyacrylamide gel electrophoresis. X-tremeGENE reagent, the BHK-21 cell line, and CuSO4 showed the highest hPSA production rates. Furthermore, BHK-21 cells were more resistant to the oxidative stress caused by 100 μM CuSO4. These results suggest that the proposed optimized inducible expression system can effectively produce recombinant proteins with desired characteristics for a wide range of applications in molecular biology. PMID:27582737

  18. Expression System Based on an MTIIa Promoter to Produce hPSA in Mammalian Cell Cultures

    Science.gov (United States)

    Santos, Anderson K.; Parreira, Ricardo C.; Resende, Rodrigo R.

    2016-01-01

    Because of the limitations of standard culture techniques, the development of new recombinant protein expression systems with biotechnological potential is a key challenge. Ideally, such systems should be able to effectively and accurately synthesize a protein of interest with intrinsic metabolic capacity. Here, we describe such a system that was designed based on a plasmid vector containing promoter elements derived from the metallothionein MTIIa promoter, as well as processing and purification elements. This promoter can be induced by heavy metals in a culture medium to induce the synthesis of human prostate-specific antigen (hPSA), which has been modified to insert elements for purification, proteolysis, and secretion. We optimized hPSA production in this system by comparing the effects and contributions of ZnCl2, CdCl2, and CuSO4 in HEK293FT, HeLa, BHK-21, and CHO-K1 cells. We also compared the effectiveness of three different transfection agents: multi-walled carbon nanotubes, Lipofectamine 2000, and X-tremeGENE HP Reagent. hPSA production was confirmed via the detection of enhanced green fluorescent protein fluorescence, and cell viability was determined. The expression of hPSA was compared with that of the native protein produced by LNCaP cells, using enzyme-linked immunosorbent assay and sodium dodecyl sulfate polyacrylamide gel electrophoresis. X-tremeGENE reagent, the BHK-21 cell line, and CuSO4 showed the highest hPSA production rates. Furthermore, BHK-21 cells were more resistant to the oxidative stress caused by 100 μM CuSO4. These results suggest that the proposed optimized inducible expression system can effectively produce recombinant proteins with desired characteristics for a wide range of applications in molecular biology. PMID:27582737

  19. Expression system based on an MTIIa promoter to produce hPSA in mammalian cell cultures

    Directory of Open Access Journals (Sweden)

    Anderson K Santos

    2016-08-01

    Full Text Available Because of the limitations of standard culture techniques, the development of new recombinant protein expression systems with biotechnological potential is a key challenge. Ideally, such systems should be able to effectively and accurately synthesize a protein of interest with intrinsic metabolic capacity. Here, we describe such a system that was designed based on a plasmid vector containing promoter elements derived from the metallothionein MTIIa promoter, as well as processing and purification elements. This promoter can be induced by heavy metals in a culture medium to induce the synthesis of human prostate-specific antigen (hPSA, which has been modified to insert elements for purification, proteolysis, and secretion. We optimized hPSA production in this system by comparing the effects and contributions of ZnCl2, CdCl2, and CuSO4 in HEK293FT, HeLa, BHK-21, and CHO-K1 cells. We also compared the effectiveness of three different transfection agents: multi-walled carbon nanotubes, Lipofectamine 2000, and X-tremeGENE HP Reagent. hPSA production was confirmed via the detection of enhanced green fluorescent protein fluorescence, and cell viability was determined. The expression of hPSA was compared with that of the native protein produced by LNCaP cells, using enzyme-linked immunosorbent assay and sodium dodecyl sulphate polyacrylamide gel electrophoresis. X-tremeGENE reagent, the BHK-21 cell line, and CuSO4 showed the highest hPSA production rates. Furthermore, BHK-21 cells were more resistant to the oxidative stress caused by 100 μM CuSO4. These results suggest that the proposed optimized inducible expression system can effectively produce recombinant proteins with desired characteristics for a wide range of applications in molecular biology.

  20. Lithium-Ion Battery Cell-Balancing Algorithm for Battery Management System Based on Real-Time Outlier Detection

    OpenAIRE

    Changhao Piao; Zhaoguang Wang; Ju Cao; Wei Zhang; Sheng Lu

    2015-01-01

    A novel cell-balancing algorithm which was used for cell balancing of battery management system (BMS) was proposed in this paper. Cell balancing algorithm is a key technology for lithium-ion battery pack in the electric vehicle field. The distance-based outlier detection algorithm adopted two characteristic parameters (voltage and state of charge) to calculate each cell’s abnormal value and then identified the unbalanced cells. The abnormal and normal type of battery cells were acquired by on...

  1. Sliding Mode Control of the Battery Bank for the Fuel Cell-based Distributed Generation System

    OpenAIRE

    Junsheng Jiao

    2013-01-01

    The dynamic models for the fuel cell power and the configuration of the fuel cell distributed generation system are shown in this paper. Due to nonlinear characteristics of fuel cell model, the output voltage of fuel cell varies greatly when the load changes. A novel interface is designed to provide a constant output voltage for charging of the battery bank of the fuel cell distributed generation. The thesis presents a sliding mode control design of PEMFC distributed generation system. A casc...

  2. Fuel Cell Power Model Version 2: Startup Guide, System Designs, and Case Studies. Modeling Electricity, Heat, and Hydrogen Generation from Fuel Cell-Based Distributed Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Steward, D.; Penev, M.; Saur, G.; Becker, W.; Zuboy, J.

    2013-06-01

    This guide helps users get started with the U.S. Department of Energy/National Renewable Energy Laboratory Fuel Cell Power (FCPower) Model Version 2, which is a Microsoft Excel workbook that analyzes the technical and economic aspects of high-temperature fuel cell-based distributed energy systems with the aim of providing consistent, transparent, comparable results. This type of energy system would provide onsite-generated heat and electricity to large end users such as hospitals and office complexes. The hydrogen produced could be used for fueling vehicles or stored for later conversion to electricity.

  3. Virtual reality based support system for layout planning and programming of an industrial robotic work cell.

    Directory of Open Access Journals (Sweden)

    Hwa Jen Yap

    Full Text Available Traditional robotic work cell design and programming are considered inefficient and outdated in current industrial and market demands. In this research, virtual reality (VR technology is used to improve human-robot interface, whereby complicated commands or programming knowledge is not required. The proposed solution, known as VR-based Programming of a Robotic Work Cell (VR-Rocell, consists of two sub-programmes, which are VR-Robotic Work Cell Layout (VR-RoWL and VR-based Robot Teaching System (VR-RoT. VR-RoWL is developed to assign the layout design for an industrial robotic work cell, whereby VR-RoT is developed to overcome safety issues and lack of trained personnel in robot programming. Simple and user-friendly interfaces are designed for inexperienced users to generate robot commands without damaging the robot or interrupting the production line. The user is able to attempt numerous times to attain an optimum solution. A case study is conducted in the Robotics Laboratory to assemble an electronics casing and it is found that the output models are compatible with commercial software without loss of information. Furthermore, the generated KUKA commands are workable when loaded into a commercial simulator. The operation of the actual robotic work cell shows that the errors may be due to the dynamics of the KUKA robot rather than the accuracy of the generated programme. Therefore, it is concluded that the virtual reality based solution approach can be implemented in an industrial robotic work cell.

  4. Virtual reality based support system for layout planning and programming of an industrial robotic work cell.

    Science.gov (United States)

    Yap, Hwa Jen; Taha, Zahari; Dawal, Siti Zawiah Md; Chang, Siow-Wee

    2014-01-01

    Traditional robotic work cell design and programming are considered inefficient and outdated in current industrial and market demands. In this research, virtual reality (VR) technology is used to improve human-robot interface, whereby complicated commands or programming knowledge is not required. The proposed solution, known as VR-based Programming of a Robotic Work Cell (VR-Rocell), consists of two sub-programmes, which are VR-Robotic Work Cell Layout (VR-RoWL) and VR-based Robot Teaching System (VR-RoT). VR-RoWL is developed to assign the layout design for an industrial robotic work cell, whereby VR-RoT is developed to overcome safety issues and lack of trained personnel in robot programming. Simple and user-friendly interfaces are designed for inexperienced users to generate robot commands without damaging the robot or interrupting the production line. The user is able to attempt numerous times to attain an optimum solution. A case study is conducted in the Robotics Laboratory to assemble an electronics casing and it is found that the output models are compatible with commercial software without loss of information. Furthermore, the generated KUKA commands are workable when loaded into a commercial simulator. The operation of the actual robotic work cell shows that the errors may be due to the dynamics of the KUKA robot rather than the accuracy of the generated programme. Therefore, it is concluded that the virtual reality based solution approach can be implemented in an industrial robotic work cell. PMID:25360663

  5. Cell-based sensor system using L6 cells for broad band continuous pollutant monitoring in aquatic environments.

    Science.gov (United States)

    Kubisch, Rebekka; Bohrn, Ulrich; Fleischer, Maximilian; Stütz, Evamaria

    2012-01-01

    Pollution of drinking water sources represents a continuously emerging problem in global environmental protection. Novel techniques for real-time monitoring of water quality, capable of the detection of unanticipated toxic and bioactive substances, are urgently needed. In this study, the applicability of a cell-based sensor system using selected eukaryotic cell lines for the detection of aquatic pollutants is shown. Readout parameters of the cells were the acidification (metabolism), oxygen consumption (respiration) and impedance (morphology) of the cells. A variety of potential cytotoxic classes of substances (heavy metals, pharmaceuticals, neurotoxins, waste water) was tested with monolayers of L6 cells (rat myoblasts). The cytotoxicity or cellular effects induced by inorganic ions (Ni(2+) and Cu(2+)) can be detected with the metabolic parameters acidification and respiration down to 0.5 mg/L, whereas the detection limit for other substances like nicotine and acetaminophen are rather high, in the range of 0.1 mg/L and 100 mg/L. In a close to application model a real waste water sample shows detectable signals, indicating the existence of cytotoxic substances. The results support the paradigm change from single substance detection to the monitoring of overall toxicity. PMID:22737014

  6. Cell-Based Sensor System Using L6 Cells for Broad Band Continuous Pollutant Monitoring in Aquatic Environments

    Directory of Open Access Journals (Sweden)

    Evamaria Stütz

    2012-03-01

    Full Text Available Pollution of drinking water sources represents a continuously emerging problem in global environmental protection. Novel techniques for real-time monitoring of water quality, capable of the detection of unanticipated toxic and bioactive substances, are urgently needed. In this study, the applicability of a cell-based sensor system using selected eukaryotic cell lines for the detection of aquatic pollutants is shown. Readout parameters of the cells were the acidification (metabolism, oxygen consumption (respiration and impedance (morphology of the cells. A variety of potential cytotoxic classes of substances (heavy metals, pharmaceuticals, neurotoxins, waste water was tested with monolayers of L6 cells (rat myoblasts. The cytotoxicity or cellular effects induced by inorganic ions (Ni2+ and Cu2+ can be detected with the metabolic parameters acidification and respiration down to 0.5 mg/L, whereas the detection limit for other substances like nicotine and acetaminophen are rather high, in the range of 0.1 mg/L and 100 mg/L. In a close to application model a real waste water sample shows detectable signals, indicating the existence of cytotoxic substances. The results support the paradigm change from single substance detection to the monitoring of overall toxicity.

  7. Innovative household systems based on solid oxide fuel cells for the Mediterranean climate

    DEFF Research Database (Denmark)

    Vialetto, Giulio; Rokni, Masoud; Noro, Marco

    2015-01-01

    .Publication of the 2004/8/EC Directive indicates that cogeneration is considered as a solution to reach the goal of energy efficiency.This paper presents an innovative system based on solid oxide fuel cells (SOFCs), an air source heat pump (ASHP), and an integration system to cover a part of the heating demand...... of a building. Two different integration systems are proposed: electric heater and condensing boiler. Heat storage is also considered to store waste heat when it is unused. An innovative parameter, the electric equivalent load, is proposed: it has the function of characterizing not only electricity consumption...... but also heating and cooling demands. The aim is to maximize efficiency while minimizing the mismatch between different forms of energy consumption. The proposal is to verify the energy efficiency of the system used to cover energy demands of a residential building located in a Mediterranean area (Trapani...

  8. A New Cogeneration Residential System Based on Solid Oxide Fuel Cells for a Northern European Climate

    DEFF Research Database (Denmark)

    Vialetto, Giulio; Rokni, Masoud

    2015-01-01

    of them received subsidies to increase installation and reduce cost. This article presents an innovative cogeneration system based on a solid oxide fuel cell (SOFC) system and heat pump for household applications with a focus on primary energy and economic savings using electric equivalent load parameter...... which is a function of the electricity and heat demand of the user, and allows different operation strategies to be considered. The proposal is to maximize the efficiency of the system and to make it profitable, even though technologies with a high purchase cost are considered. Simulations of the system...... are performed under different strategies at a resort located in a northern European climate (Denmark) to cover electricity, space heating and domestic hot water (DHW) demands. The results of these simulations are analyzed with thermodynamic and techno-economic benchmarks, considering different economic...

  9. Rescue the failed half-ZFN by a sensitive mammalian cell-based luciferase reporter system.

    Directory of Open Access Journals (Sweden)

    Weifeng Zhang

    Full Text Available ZFN technology is a powerful research tool and has been used for genome editing in cells lines, animals and plants. The generation of functional ZFNs for particular targets in mammalian genome is still challenging for an average research group. The modular-assembly method is relatively fast, easy-to-practice but has a high failure rate. Some recent studies suggested that a ZFP with low binding activity might be able to form a working ZFN pair with another binding active half-ZFP. In order to unveil the potential ZFP candidates among those with low binding activities, this paper established a highly sensitive mammalian cell-based transcriptional reporter system to assess the DNA binding activities of ZFPs by inserting multiple copies of ZFN target sequence fragment (TSF of an interested gene (e. g., hPGRN or hVEGF. Our results showed that this system increased the screening sensitivity up to 50-fold and markedly amplified the differences in the binding activities between different ZFPs. We also found that the targeted chromosomal gene repair efficiency of each hPGRN or hVEGF ZFN pair was in proportion with the combination of the binding activities of the ZFL (Left zinc finger and ZFR (Right zinc finger. A hPGRN ZFR with low binding ability was able to form a biological active ZFN if combined with a hPGRN ZFL with relatively high binding ability. Lastly, site-specific genome editing by hPGRN ZFNs generated by this system was confirmed by sequencing, and the PGRN knock-out cell line showed significantly decreased cell growth compared with the control. Our system will provide a valuable tool for further optimizing the nucleases with regard to specificity and cytotoxicity.

  10. Micro-electro-mechanical systems (MEMS)-based micro-scale direct methanol fuel cell development

    International Nuclear Information System (INIS)

    This paper describes a high-power density, silicon-based micro-scale direct methanol fuel cell (DMFC), under development at Carnegie Mellon. Major issues in the DMFC design include the water management and energy-efficient micro fluidic sub-systems. The air flow and the methanol circulation are both at a natural draft, while a passive liquid-gas separator removes CO2 from the methanol chamber. An effective approach for maximizing the DMFC energy density, pumping the excess water back to the anode, is illustrated. The proposed DMFC contains several unique features: a silicon wafer with arrays of etched holes selectively coated with a non-wetting agent for collecting water at the cathode; a silicon membrane micro pump for pumping the collected water back to the anode; and a passive liquid-gas separator for CO2 removal. All of these silicon-based components are fabricated using micro-electro-mechanical systems (MEMS)-based processes on the same silicon wafer, so that interconnections are eliminated, and integration efforts as well as post-fabrication costs are both minimized. The resulting fuel cell has an overall size of one cubic inch, produces a net output of 10 mW, and has an energy density three to five times higher than that of current lithium-ion batteries

  11. Innovative Household Systems Based on Solid Oxide Fuel Cells for a Northern European climate

    DEFF Research Database (Denmark)

    Rokni, Masoud; Vialetto, Giulio

    2015-01-01

    Energy saving is an open point in most European countries where energy policies are oriented to reduce the use of fossil fuels, greenhouses emissions and energy independence and to increase the use of renewable energies. In the last several years, new technologies have been developed, and some...... of them received subsidies to increase installation and reduce cost.This article presents an innovative cogeneration system based on a solid oxide fuel cell (SOFC) systemand heat pump for household applications with a focus on primary energy and economic savings using electric equivalent load parameter...

  12. Naturally derived materials-based cell and drug delivery systems in skin regeneration.

    Science.gov (United States)

    Huang, Sha; Fu, Xiaobing

    2010-03-01

    The objective of regenerative medicine is to provide cells with a local environment of artificial extracellular matrix where they can proliferate and differentiate efficiently and therefore, induce the repair of defective tissues according to the natural healing potential of patients. For this purpose, naturally derived materials are being widely used because of their similarities to the extracellular matrix, typically good biocharacteristics and inherent cellular interaction. Also, natural polymers can be engineered to release growth factors and related agents in response to physiologic signals to imitate the natural healing process and to promote fast tissue regeneration and reduce scarring in wounds. Although synthetic materials have been used extensively in tissue engineering fields, this review illustrates the contribution of natural materials and natural materials-based protein delivery systems to regenerative medicine research, with emphasis on the application of multifunctional vehicles for cell and growth factor delivery in skin regeneration research. PMID:19850093

  13. Models and methods for design and implementation of computer based control and monitoring systems for production cells

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk

    based control and monitoring systems for production cells.The manufacturing environment and the current practice for engineering of cells control systems are described and automation software enablers are discussed. A number of problems related to these issues are identified. In order to support...... engineering of cell control systems by the use of enablers, a generic cell control data model and an architecture are defined. Further, an engineering methodology is defined. The three element enablers, architecture and methodology consitutes the Cell Control Engineering concept which is defined and evaluated......This dissertation is concerned with the engineering, i.e. the designing and making, of industrial cell control systems. The focus is on automated robot welding cells in the shipbuilding industry. The industrial research project defines models and methods for design and implementation of computer...

  14. Systemic Administration of Interleukin 2 Enhances the Therapeutic Efficacy of Dendritic Cell-Based Tumor Vaccines

    Science.gov (United States)

    Shimizu, K.; Fields, R. C.; Giedlin, M.; Mule, J. J.

    1999-03-01

    We have reported previously that murine bone marrow-derived dendritic cells (DC) pulsed with whole tumor lysates can mediate potent antitumor immune responses both in vitro and in vivo. Because successful therapy was dependent on host immune T cells, we have now evaluated whether the systemic administration of the T cell stimulatory/growth promoting cytokine interleukin-2 (IL-2) could enhance tumor lysate-pulsed DC-based immunizations to further promote protective immunity toward, and therapeutic rejection of, syngeneic murine tumors. In three separate approaches using a weakly immunogenic sarcoma (MCA-207), the systemic administration of non-toxic doses of recombinant IL-2 (20,000 and 40,000 IU/dose) was capable of mediating significant increases in the potency of DC-based immunizations. IL-2 could augment the efficacy of tumor lysate-pulsed DC to induce protective immunity to lethal tumor challenge as well as enhance splenic cytotoxic T lymphocyte activity and interferon-γ production in these treated mice. Moreover, treatment with the combination of tumor lysate-pulsed DC and IL-2 could also mediate regressions of established pulmonary 3-day micrometastases and 7-day macrometastases as well as established 14- and 28-day s.c. tumors, leading to either significant cure rates or prolongation in overall survival. Collectively, these findings show that nontoxic doses of recombinant IL-2 can potentiate the antitumor effects of tumor lysate-pulsed DC in vivo and provide preclinical rationale for the use of IL-2 in DC-based vaccine strategies in patients with advanced cancer.

  15. An organic transistor-based system for reference-less electrophysiological monitoring of excitable cells

    Science.gov (United States)

    Spanu, A.; Lai, S.; Cosseddu, P.; Tedesco, M.; Martinoia, S.; Bonfiglio, A.

    2015-03-01

    In the last four decades, substantial advances have been done in the understanding of the electrical behavior of excitable cells. From the introduction in the early 70's of the Ion Sensitive Field Effect Transistor (ISFET), a lot of effort has been put in the development of more and more performing transistor-based devices to reliably interface electrogenic cells such as, for example, cardiac myocytes and neurons. However, depending on the type of application, the electronic devices used to this aim face several problems like the intrinsic rigidity of the materials (associated with foreign body rejection reactions), lack of transparency and the presence of a reference electrode. Here, an innovative system based on a novel kind of organic thin film transistor (OTFT), called organic charge modulated FET (OCMFET), is proposed as a flexible, transparent, reference-less transducer of the electrical activity of electrogenic cells. The exploitation of organic electronics in interfacing the living matters will open up new perspectives in the electrophysiological field allowing us to head toward a modern era of flexible, reference-less, and low cost probes with high-spatial and high-temporal resolution for a new generation of in-vitro and in-vivo monitoring platforms.

  16. Fuel-Cell Power Systems Incorporating Mg-Based H2 Generators

    Science.gov (United States)

    Kindler, Andrew; Narayan, Sri R.

    2009-01-01

    Two hydrogen generators based on reactions involving magnesium and steam have been proposed as means for generating the fuel (hydrogen gas) for such fuel-cell power systems as those to be used in the drive systems of advanced motor vehicles. The hydrogen generators would make it unnecessary to rely on any of the hydrogen storage systems developed thus far that are, variously, too expensive, too heavy, too bulky, and/or too unsafe to be practical. The two proposed hydrogen generators are denoted basic and advanced, respectively. In the basic hydrogen generator (see figure), steam at a temperature greater than or equals 330 C would be fed into a reactor charged with magnesium, wherein hydrogen would be released in the exothermic reaction Mg + H2O yields MgO + H2. The steam would be made in a flash boiler. To initiate the reaction, the boiler could be heated electrically by energy borrowed from a storage battery that would be recharged during normal operation of the associated fuel-cell subsystem. Once the reaction was underway, heat from the reaction would be fed to the boiler. If the boiler were made an integral part of the hydrogen-generator reactor vessel, then the problem of transfer of heat from the reactor to the boiler would be greatly simplified. A pump would be used to feed water from a storage tank to the boiler.

  17. A microdroplet cell culture based high frequency somatic embryogenesis system for pigeonpea, Cajanus cajan (L.) Millsp.

    Science.gov (United States)

    Kumar, Nagan Udhaya; Gnanaraj, Muniraj; Sindhujaa, Vajravel; Viji, Maluventhen; Manoharan, Kumariah

    2015-09-01

    A protocol for high frequency production of somatic embryos was worked out in pigeonpea, Cajanus cajan (L.) Millsp. The protocol involved sequential employment of embryogenic callus cultures, low density cell suspension cultures and a novel microdroplet cell culture system. The microdroplet cell cultures involved culture of a single cell in 10 μI of Murashige and Skoog's medium supplemented with phytohormones, growth factors and phospholipid precursors. By employing the microdroplet cell cultures, single cells in isolation were grown into cell clones which developed somatic embryos. Further, 2,4-dichlorophenoxyacetic acid, kinetin, polyethylene glycol, putrescine, spermine, spermidine, choline chloride, ethanolamine and LiCl were supplemented to the low density cell suspension cultures and microdroplet cell cultures to screen for their cell division and somatic embryogenesis activity. Incubation of callus or the inoculum employed for low density cell suspension cultures and microdroplet cell cultures with polyethylene glycol was found critical for induction of somatic embryogenesis. Somatic embryogenesis at a frequency of 1.19, 3.16 and 6.51 per 10(6) cells was achieved in the callus, low density cell suspension cultures and microdroplet cell cultures, respectively. Advantages of employing microdroplet cell cultures for high frequency production of somatic embryos and its application in genetic transformation protocols are discussed. PMID:26548080

  18. Incubator embedded cell culture imaging system (EmSight) based on Fourier ptychographic microscopy

    OpenAIRE

    Kim, Jinho; Henley, Beverley M.; Kim, Charlene H.; Lester, Henry A.; Yang, Changhuei

    2016-01-01

    Multi-day tracking of cells in culture systems can provide valuable information in bioscience experiments. We report the development of a cell culture imaging system, named EmSight, which incorporates multiple compact Fourier ptychographic microscopes with a standard multiwell imaging plate. The system is housed in an incubator and presently incorporates six microscopes. By using the same low magnification objective lenses as the objective and the tube lens, the EmSight is configured as a 1:1...

  19. An Easy-to-Use Polystyrene Microchip-based Cell Culture System.

    Science.gov (United States)

    Tazawa, Hidekatsu; Sunaoshi, Shohei; Tokeshi, Manabu; Kitamori, Takehiko; Ohtani-Kaneko, Ritsuko

    2016-01-01

    In this study, we developed an integrated, low-cost microfluidic cell culture system that is easy to use. This system consists of a disposable polystyrene microchip, a polytetrafluoroethylene valve, an air bubble trap, and an indium tin oxide temperature controller. Valve pressure resistance was validated with a manometer to be 3 MPa. The trap protected against bubble contamination. The temperature controller enabled the culture of Macaca mulatta RF/6A 135 vascular endothelial cells, which are difficult to culture in glass microchips, without a CO2 incubator. We determined the optimal coating conditions for these cells and were able to achieve stable, confluent culture within 1 week. This practical system is suitable for low-cost screening and has potential applications as circulatory cell culture systems and research platforms in cell biology. PMID:26960617

  20. Possible configurations for an air independent propulsion (AIP) system for submarines based on fuel cells

    International Nuclear Information System (INIS)

    'Full text:' Conventional submarines employ an electric propulsion system, based on energy storage in batteries which are recharged using diesel motors connected to generator alternators. This limits their autonomy underwater given that it will be depend on the amount of energy that can be stored in the batteries; currently, a normal value is to have energy to navigate for three days at low speed. As of from the WWII, several shipyards began to carry out research on propulsion systems for submarines that would be capable of operating under anaerobic conditions, independent of the air (AIP Systems). Since then, several proposals have been considered, but there is one option that several navies are currently putting their trust in: fuel cells. The objective of this Project is to stress the different configurations that can be considered to this end, as regards the transportation of hydrogen and oxygen. From the hydrogen point of view, the possibilities of transporting it in metal hydrides or its on-board production through the reforming of different fuels (gas-oil, ethanol, methanol), are analyzed. This study also compares auxiliary systems (including CO2 removers), and proposes solutions, some of which are under development, indicating which are currently being considered to a greater extent. (author)

  1. Sliding Mode Control of the Battery Bank for the Fuel Cell-based Distributed Generation System

    Directory of Open Access Journals (Sweden)

    Junsheng Jiao

    2013-07-01

    Full Text Available The dynamic models for the fuel cell power and the configuration of the fuel cell distributed generation system are shown in this paper. Due to nonlinear characteristics of fuel cell model, the output voltage of fuel cell varies greatly when the load changes. A novel interface is designed to provide a constant output voltage for charging of the battery bank of the fuel cell distributed generation. The thesis presents a sliding mode control design of PEMFC distributed generation system. A cascaded control structure is chosen for ease of control realization and to exploit the motion separation property of power converters. The simulation results confirm the output current and voltage of the PEM fuel cell array converge rapidly to their reference values.

  2. Systems-based technologies in profiling the stem cell molecular framework for cardioregenerative medicine

    OpenAIRE

    Wyles, Saranya P.; Faustino, Randolph S.; Li, Xing; Terzic, Andre; Nelson, Timothy J.

    2015-01-01

    Over the last decade, advancements in stem cell biology have yielded a variety of sources for stem cell-based cardiovascular investigation. Stem cell behavior, whether to maintain its stable state of pluripotency or to prime toward the cardiovascular lineage is governed by a set of coordinated interactions between epigenetic, transcriptional, and translational mechanisms. The science of incorporating genes (genomics), RNA (transcriptomics), proteins (proteomics), and metabolites (metabolomics...

  3. The modeling and simulation of thermal based modified solid oxide fuel cell (SOFC) for grid-connected systems

    OpenAIRE

    Ayetül Gelen; Tankut Yalcinoz

    2015-01-01

    This paper presents a thermal based modified dynamic model of a Solid Oxide Fuel Cell (SOFC) for grid-connected systems. The proposed fuel cell model involves ohmic, activation and concentration voltage losses, thermal dynamics, methanol reformer, fuel utilization factor and power limiting module. A power conditioning unit (PCU), which consists of a DC-DC boost converter and a DC-AC voltage-source inverter (VSI), their controller, transformer and filter, is designed for grid-connected systems...

  4. Miniaturized Mass-Spectrometry-Based Analysis System for Fully Automated Examination of Conditioned Cell Culture Media

    NARCIS (Netherlands)

    Weber, E.; Pinkse, M.W.H.; Bener-Aksam, E.; Vellekoop, M.J.; Verhaert, P.D.E.M.

    2012-01-01

    We present a fully automated setup for performing in-line mass spectrometry (MS) analysis of conditioned media in cell cultures, in particular focusing on the peptides therein. The goal is to assess peptides secreted by cells in different culture conditions. The developed system is compatible with M

  5. Optimizing Dendritic Cell-Based Immunotherapy: Tackling the Complexity of Different Arms of the Immune System

    Directory of Open Access Journals (Sweden)

    Ilse Van Brussel

    2012-01-01

    Full Text Available Earlier investigations have revealed a surprising complexity and variety in the range of interaction between cells of the innate and adaptive immune system. Our understanding of the specialized roles of dendritic cell (DC subsets in innate and adaptive immune responses has been significantly advanced over the years. Because of their immunoregulatory capacities and because very small numbers of activated DC are highly efficient at generating immune responses against antigens, DCs have been vigorously used in clinical trials in order to elicit or amplify immune responses against cancer and chronic infectious diseases. A better insight in DC immunobiology and function has stimulated many new ideas regarding the potential ways forward to improve DC therapy in a more fundamental way. Here, we discuss the continuous search for optimal in vitro conditions in order to generate clinical-grade DC with a potent immunogenic potential. For this, we explore the molecular and cellular mechanisms underlying adequate immune responses and focus on most favourable DC culture regimens and activation stimuli in humans. We envisage that by combining each of the features outlined in the current paper into a unified strategy, DC-based vaccines may advance to a higher level of effectiveness.

  6. A recourse-based solution approach to the design of fuel cell aeropropulsion systems

    Science.gov (United States)

    Choi, Taeyun Paul

    outcome of uncertainties to another. On the contrary, what would be more valuable given the time-phased nature of engineering design is the capability to perform an anticipatory identification of an optimum that is also expected to incur the least costly recourse option in the future. It is argued that such a solution is in fact a more balanced alternative than robust, probabilistically maximized, or chance-constrained solutions, because it represents trading the design optimality in the present with the potential costs of future recourse. Therefore, it is further proposed that the original two-stage model be embedded inside a larger design loop, so that the realization of numerous recourse scenarios can be simulated for a given first-stage design. The repetitive procedure at the second stage is necessary for computing the expected cost of recourse, which is equivalent to its mathematical expectation as per the strong law of large numbers. The feedback loop then communicates this information to the aggregate-level optimizer, whose objective is to minimize the sum total of the first-stage metric and the expected cost of future corrective actions. The resulting stochastic solution is a design that is well-hedged against the uncertain consequences of later design phases, while at the same time being less conservative than a solution designed to more traditional deterministic standards. As a proof-of-concept demonstration, the recourse-based solution approach is presented as applied to a contemporary aerospace engineering problem of interest - the integration of fuel cell technology into uninhabited aerial systems. The creation of a simulation environment capable of designing three system alternatives based on Proton Exchange Membrane Fuel Cell (PEMFC) technology and another three systems leveraging upon Solid Oxide Fuel Cell (SOFC) technology is presented as the means to notionally emulate the development process of this revolutionary aeropropulsion method. Notable findings

  7. Human Pluripotent Stem Cell Based Developmental Toxicity Assays for Chemical Safety Screening and Systems Biology Data Generation.

    Science.gov (United States)

    Shinde, Vaibhav; Klima, Stefanie; Sureshkumar, Perumal Srinivasan; Meganathan, Kesavan; Jagtap, Smita; Rempel, Eugen; Rahnenführer, Jörg; Hengstler, Jan Georg; Waldmann, Tanja; Hescheler, Jürgen; Leist, Marcel; Sachinidis, Agapios

    2015-01-01

    Efficient protocols to differentiate human pluripotent stem cells to various tissues in combination with -omics technologies opened up new horizons for in vitro toxicity testing of potential drugs. To provide a solid scientific basis for such assays, it will be important to gain quantitative information on the time course of development and on the underlying regulatory mechanisms by systems biology approaches. Two assays have therefore been tuned here for these requirements. In the UKK test system, human embryonic stem cells (hESC) (or other pluripotent cells) are left to spontaneously differentiate for 14 days in embryoid bodies, to allow generation of cells of all three germ layers. This system recapitulates key steps of early human embryonic development, and it can predict human-specific early embryonic toxicity/teratogenicity, if cells are exposed to chemicals during differentiation. The UKN1 test system is based on hESC differentiating to a population of neuroectodermal progenitor (NEP) cells for 6 days. This system recapitulates early neural development and predicts early developmental neurotoxicity and epigenetic changes triggered by chemicals. Both systems, in combination with transcriptome microarray studies, are suitable for identifying toxicity biomarkers. Moreover, they may be used in combination to generate input data for systems biology analysis. These test systems have advantages over the traditional toxicological studies requiring large amounts of animals. The test systems may contribute to a reduction of the costs for drug development and chemical safety evaluation. Their combination sheds light especially on compounds that may influence neurodevelopment specifically. PMID:26132533

  8. Antireflective Nanocomposite Based Coating on Crystalline Silicon Solar Cells for Building-Integrated Photovoltaic Systems

    OpenAIRE

    Gangopadhyay, Utpal; Jana, Sukhendu; Das, Sayan; Garain, Sutapa; Ray, Soma

    2013-01-01

    Building-integrated photovoltaic (BIPV) systems represent an interesting, alternative approach for increasing the available area for electricity production and potentially for further reducing the cost of solar electricity. In BIPV systems, the visual impression of a solar module becomes important, including its color. However, the range of solar cell colours and shapes currently on offer to architects and BIPV system designers is still very limited, and this is a barrier to the widespread us...

  9. Sleeping Beauty transposon-based system for rapid generation of HBV-replicating stable cell lines.

    Science.gov (United States)

    Wu, Yong; Zhang, Tian-Ying; Fang, Lin-Lin; Chen, Zi-Xuan; Song, Liu-Wei; Cao, Jia-Li; Yang, Lin; Yuan, Quan; Xia, Ning-Shao

    2016-08-01

    The stable HBV-replicating cell lines, which carry replication-competent HBV genome stably integrated into the genome of host cell, are widely used to evaluate the effects of antiviral agents. However, current methods to generate HBV-replicating cell lines, which are mostly dependent on random integration of foreign DNA via plasmid transfection, are less-efficient and time-consuming. To address this issue, we constructed an all-in-one Sleeping Beauty transposon system (denoted pTSMP-HBV vector) for robust generation of stable cell lines carrying replication-competent HBV genome of different genotype. This vector contains a Sleeping Beauty transposon containing HBV 1.3-copy genome with an expression cassette of the SV40 promoter driving red fluorescent protein (mCherry) and self-cleaving P2A peptide linked puromycin resistance gene (PuroR). In addition, a PGK promoter-driven SB100X hyperactive transposase cassette is placed in the outside of the transposon in the same plasmid.The HBV-replicating stable cells could be obtained from pTSMP-HBV transfected HepG2 cells by red fluorescence-activated cell sorting and puromycin resistant cell selection within 4-week. Using this system, we successfully constructed four cell lines carrying replication-competent HBV genome of genotypes A-D. The replication and viral protein expression profiles of these cells were systematically characterized. In conclusion, our study provides a high-efficiency strategy to generate HBV-replicating stable cell lines, which may facilitate HBV-related virological study.

  10. Sleeping Beauty transposon-based system for rapid generation of HBV-replicating stable cell lines.

    Science.gov (United States)

    Wu, Yong; Zhang, Tian-Ying; Fang, Lin-Lin; Chen, Zi-Xuan; Song, Liu-Wei; Cao, Jia-Li; Yang, Lin; Yuan, Quan; Xia, Ning-Shao

    2016-08-01

    The stable HBV-replicating cell lines, which carry replication-competent HBV genome stably integrated into the genome of host cell, are widely used to evaluate the effects of antiviral agents. However, current methods to generate HBV-replicating cell lines, which are mostly dependent on random integration of foreign DNA via plasmid transfection, are less-efficient and time-consuming. To address this issue, we constructed an all-in-one Sleeping Beauty transposon system (denoted pTSMP-HBV vector) for robust generation of stable cell lines carrying replication-competent HBV genome of different genotype. This vector contains a Sleeping Beauty transposon containing HBV 1.3-copy genome with an expression cassette of the SV40 promoter driving red fluorescent protein (mCherry) and self-cleaving P2A peptide linked puromycin resistance gene (PuroR). In addition, a PGK promoter-driven SB100X hyperactive transposase cassette is placed in the outside of the transposon in the same plasmid.The HBV-replicating stable cells could be obtained from pTSMP-HBV transfected HepG2 cells by red fluorescence-activated cell sorting and puromycin resistant cell selection within 4-week. Using this system, we successfully constructed four cell lines carrying replication-competent HBV genome of genotypes A-D. The replication and viral protein expression profiles of these cells were systematically characterized. In conclusion, our study provides a high-efficiency strategy to generate HBV-replicating stable cell lines, which may facilitate HBV-related virological study. PMID:27091097

  11. Increasing the sensitivity for stem cell monitoring in system-function based magnetic particle imaging

    Science.gov (United States)

    Them, Kolja; Salamon, J.; Szwargulski, P.; Sequeira, S.; Kaul, M. G.; Lange, C.; Ittrich, H.; Knopp, Tobias

    2016-05-01

    The use of superparamagnetic iron oxide nanoparticles (SPIONs) has provided new possibilities in biophysics and biomedical imaging technologies. The magnetization dynamics of SPIONs, which can be influenced by the environment, are of central interest. In this work, different biological SPION environments are used to investigate three different calibration methods for stem cell monitoring in magnetic particle imaging. It is shown that calibrating using SPIONs immobilized via agarose gel or intracellular uptake results in superior stem cell image quality compared to mobile SPIONs in saline. This superior image quality enables more sensitive localization and identification of a significantly smaller number of magnetically labeled stem cells. The results are important for cell tracking and monitoring of future SPION based therapies such as hyperthermia based cancer therapies, targeted drug delivery, or tissue regeneration approaches where it is crucial to image a sufficiently small number of SPIONs interacting with biological matter.

  12. A new procedure for estimating the cell temperature of a high concentrator photovoltaic grid connected system based on atmospheric parameters

    International Nuclear Information System (INIS)

    Highlights: • Concentrating grid-connected systems are working at maximum power point. • The operating cell temperature is inherently lower than at open circuit. • Two novel methods for estimating the cell temperature are proposed. • Both predict the operating cell temperature from atmospheric parameters. • Experimental results show that both methods perform effectively. - Abstract: The working cell temperature of high concentrator photovoltaic systems is a crucial parameter when analysing their performance and reliability. At the same time, due to the special features of this technology, the direct measurement of the cell temperature is very complex and is usually obtained by using different indirect methods. High concentrator photovoltaic modules in a system are operating at maximum power since they are connected to an inverter. So that, their cell temperature is lower than the cell temperature of a module at open-circuit voltage since an important part of the light power density is converted into electricity. In this paper, a procedure for indirectly estimating the cell temperature of a high concentrator photovoltaic system from atmospheric parameters is addressed. Therefore, this new procedure has the advantage that is valid for estimating the cell temperature of a system at any location of interest if the atmospheric parameters are available. To achieve this goal, two different methods are proposed: one based on simple mathematical relationships and another based on artificial intelligent techniques. Results show that both methods predicts the cell temperature of a module connected to an inverter with a low margin of error with a normalised root mean square error lower or equal than 3.3%, an absolute root mean square error lower or equal than 2 °C, a mean absolute error lower or equal then 1.5 °C, and a mean bias error and a mean relative error almost equal to 0%

  13. Evaluation of a Passive Heat Exchanger Based Cooling System for Fuel Cell Applications

    Science.gov (United States)

    Colozza, Anthony J.; Burke, Kenneth A.

    2011-01-01

    Fuel cell cooling is conventionally performed with an actively controlled, dedicated coolant loop that exchanges heat with a separate external cooling loop. To simplify this system the concept of directly cooling a fuel cell utilizing a coolant loop with a regenerative heat exchanger to preheat the coolant entering the fuel cell with the coolant exiting the fuel cell was analyzed. The preheating is necessary to minimize the temperature difference across the fuel cell stack. This type of coolant system would minimize the controls needed on the coolant loop and provide a mostly passive means of cooling the fuel cell. The results indicate that an operating temperature of near or greater than 70 C is achievable with a heat exchanger effectiveness of around 90 percent. Of the heat exchanger types evaluated with the same type of fluid on the hot and cold side, a counter flow type heat exchanger would be required which has the possibility of achieving the required effectiveness. The number of heat transfer units required by the heat exchanger would be around 9 or greater. Although the analysis indicates the concept is feasible, the heat exchanger design would need to be developed and optimized for a specific fuel cell operation in order to achieve the high effectiveness value required.

  14. Impurity of stem cell graft by murine embryonic fibroblasts – implications for cell-based therapy of the central nervous system

    Directory of Open Access Journals (Sweden)

    Marek eMolcanyi

    2014-09-01

    Full Text Available Stem cells have been demonstrated to possess a therapeutic potential in experimental models of various central nervous system disorders, including stroke. The types of implanted cells appear to play a crucial role. Previously, groups of the stem cell network NRW implemented a feeder-based cell line within the scope of their projects, examining the implantation of stem cells after ischemic stroke and traumatic brain injury. Retrospective evaluation indicated the presence of spindle-shaped cells in several grafts implanted in injured animals, which indicated potential contamination by co-cultured feeder cells (murine embryonic fibroblasts – MEFs. Because feeder-based cell lines have been previously exposed to a justified criticism with regard to contamination by animal glycans, we aimed to evaluate the effects of stem cell/MEF co-transplantation. MEFs accounted for 5.33% ± 2.81 of all cells in the primary FACS-evaluated co-culture. Depending on the culture conditions and subsequent purification procedure, the MEF-fraction ranged from 0.9 to 9.9% of the cell suspensions in vitro. MEF survival and related formation of extracellular substances in vivo were observed after implantation into the uninjured rat brain. Impurity of the stem cell graft by MEFs interferes with translational strategies, which represents a threat to the potential recipient and may affect the graft microenvironment. The implications of these findings are critically discussed.

  15. Stem and Progenitor Cell-Based Therapy of the Central Nervous System

    DEFF Research Database (Denmark)

    Goldman, Steven A

    2016-01-01

    A variety of neurological disorders are attractive targets for stem and progenitor cell-based therapy. Yet many conditions are not, whether by virtue of an inhospitable disease environment, poorly understood pathophysiology, or poor alignment of donor cell capabilities with patient needs. Moreover......, some disorders may be medically feasible targets but are not practicable, in light of already available treatments, poor risk-benefit and cost-benefit profiles, or resource limitations. This Perspective seeks to define those neurological conditions most appropriate for cell replacement therapy...

  16. Current status of fuel cell based combined heat and power systems for residential sector

    Science.gov (United States)

    Ellamla, Harikishan R.; Staffell, Iain; Bujlo, Piotr; Pollet, Bruno G.; Pasupathi, Sivakumar

    2015-10-01

    Combined Heat and Power (CHP) is the sequential or simultaneous generation of multiple forms of useful energy, usually electrical and thermal, in a single and integrated system. Implementing CHP systems in the current energy sector may solve energy shortages, climate change and energy conservation issues. This review paper is divided into six sections: the first part defines and classifies the types of fuel cell used in CHP systems; the second part discusses the current status of fuel cell CHP (FC-CHP) around the world and highlights the benefits and drawbacks of CHP systems; the third part focuses on techniques for modelling CHP systems. The fourth section gives a thorough comparison and discussion of the two main fuel cell technologies used in FC-CHP (PEMFC and SOFC), characterising their technical performance and recent developments from the major manufacturers. The fifth section describes all the main components of FC-CHP systems and explains the issues connected with their practical application. The last part summarises the above, and reflects on micro FC-CHP system technology and its future prospects.

  17. Implementing oxygen control in chip-based cell and tissue culture systems.

    Science.gov (United States)

    Oomen, Pieter E; Skolimowski, Maciej D; Verpoorte, Elisabeth

    2016-09-21

    Oxygen is essential in the energy metabolism of cells, as well as being an important regulatory parameter influencing cell differentiation and function. Interest in precise oxygen control for in vitro cultures of tissues and cells continues to grow, especially with the emergence of the organ-on-a-chip and the desire to emulate in vivo conditions. This was recently discussed in this journal in a Critical Review by Brennan et al. (Lab Chip (2014). DOI: ). Microfluidics can be used to introduce flow to facilitate nutrient supply to and waste removal from in vitro culture systems. Well-defined oxygen gradients can also be established. However, cells can quickly alter the oxygen balance in their vicinity. In this Tutorial Review, we expand on the Brennan paper to focus on the implementation of oxygen analysis in these systems to achieve continuous monitoring. Both electrochemical and optical approaches for the integration of oxygen monitoring in microfluidic tissue and cell culture systems will be discussed. Differences in oxygen requirements from one organ to the next are a challenging problem, as oxygen delivery is limited by its uptake into medium. Hence, we discuss the factors determining oxygen concentrations in solutions and consider the possible use of artificial oxygen carriers to increase dissolved oxygen concentrations. The selection of device material for applications requiring precise oxygen control is discussed in detail, focusing on oxygen permeability. Lastly, a variety of devices is presented, showing the diversity of approaches that can be employed to control and monitor oxygen concentrations in in vitro experiments.

  18. Systemic therapy for selected skull base sarcomas: Chondrosarcoma, chordoma, giant cell tumour and solitary fibrous tumour/hemangiopericytoma.

    Science.gov (United States)

    Colia, Vittoria; Provenzano, Salvatore; Hindi, Nadia; Casali, Paolo G; Stacchiotti, Silvia

    2016-01-01

    This review highlights the data currently available on the activity of systemic therapy in chondrosarcoma, chordoma, giant cell tumour of the bone (GCTB) and solitary fibrous tumour, i.e., four rare sarcomas amongst mesenchymal malignancy arising from the skull base.

  19. Systemic therapy for selected skull base sarcomas: Chondrosarcoma, chordoma, giant cell tumour and solitary fibrous tumour/hemangiopericytoma.

    Science.gov (United States)

    Colia, Vittoria; Provenzano, Salvatore; Hindi, Nadia; Casali, Paolo G; Stacchiotti, Silvia

    2016-01-01

    This review highlights the data currently available on the activity of systemic therapy in chondrosarcoma, chordoma, giant cell tumour of the bone (GCTB) and solitary fibrous tumour, i.e., four rare sarcomas amongst mesenchymal malignancy arising from the skull base. PMID:27330421

  20. Clinical-Grade Manufacturing of Therapeutic Human Mesenchymal Stem/Stromal Cells in Microcarrier-Based Culture Systems.

    Science.gov (United States)

    Fernandes-Platzgummer, Ana; Carmelo, Joana G; da Silva, Cláudia Lobato; Cabral, Joaquim M S

    2016-01-01

    The therapeutic potential of mesenchymal stem/stromal cells (MSC) has triggered the need for high cell doses in a vast number of clinical applications. This demand requires the development of good manufacturing practices (GMP)-compliant ex vivo expansion protocols that should be effective to deliver a robust and reproducible supply of clinical-grade cells in a safe and cost-effective manner. Controlled stirred-tank bioreactor systems under xenogeneic (xeno)-free culture conditions offer ideal settings to develop and optimize cell manufacturing to meet the standards and needs of human MSC for cellular therapies. Herein we describe two microcarrier-based stirred culture systems using spinner flasks and controlled stirred-tank bioreactors under xeno-free conditions for the efficient ex vivo expansion of human bone marrow and adipose tissue-derived MSC. PMID:27236684

  1. Incubator embedded cell culture imaging system (EmSight) based on Fourier ptychographic microscopy.

    Science.gov (United States)

    Kim, Jinho; Henley, Beverley M; Kim, Charlene H; Lester, Henry A; Yang, Changhuei

    2016-08-01

    Multi-day tracking of cells in culture systems can provide valuable information in bioscience experiments. We report the development of a cell culture imaging system, named EmSight, which incorporates multiple compact Fourier ptychographic microscopes with a standard multiwell imaging plate. The system is housed in an incubator and presently incorporates six microscopes. By using the same low magnification objective lenses as the objective and the tube lens, the EmSight is configured as a 1:1 imaging system that, providing large field-of-view (FOV) imaging onto a low-cost CMOS imaging sensor. The EmSight improves the image resolution by capturing a series of images of the sample at varying illumination angles; the instrument reconstructs a higher-resolution image by using the iterative Fourier ptychographic algorithm. In addition to providing high-resolution brightfield and phase imaging, the EmSight is also capable of fluorescence imaging at the native resolution of the objectives. We characterized the system using a phase Siemens star target, and show four-fold improved coherent resolution (synthetic NA of 0.42) and a depth of field of 0.2 mm. To conduct live, long-term dopaminergic neuron imaging, we cultured ventral midbrain from mice driving eGFP from the tyrosine hydroxylase promoter. The EmSight system tracks movements of dopaminergic neurons over a 21 day period. PMID:27570701

  2. Stem cell-based microphysiological osteochondral system to model tissue response to interleukin-1β.

    Science.gov (United States)

    Lin, Hang; Lozito, Thomas P; Alexander, Peter G; Gottardi, Riccardo; Tuan, Rocky S

    2014-07-01

    Osteoarthritis (OA) is a chronic degenerative disease of the articular joint that involves both bone and cartilage degenerative changes. An engineered osteochondral tissue within physiological conditions will be of significant utility in understanding the pathogenesis of OA and testing the efficacy of potential disease-modifying OA drugs (DMOADs). In this study, a multichamber bioreactor was fabricated and fitted into a microfluidic base. When the osteochondral construct is inserted, two chambers are formed on either side of the construct (top, chondral; bottom, osseous) that is supplied by different medium streams. These medium conduits are critical to create tissue-specific microenvironments in which chondral and osseous tissues will develop and mature. Human bone marrow stem cell (hBMSCs)-derived constructs were fabricated in situ and cultured within the bioreactor and induced to undergo spatially defined chondrogenic and osteogenic differentiation for 4 weeks in tissue-specific media. We observed tissue specific gene expression and matrix production as well as a basophilic interface suggesting a developing tidemark. Introduction of interleukin-1β (IL-1β) to either the chondral or osseous medium stream induced stronger degradative responses locally as well as in the opposing tissue type. For example, IL-1β treatment of the osseous compartment resulted in a strong catabolic response in the chondral layer as indicated by increased matrix metalloproteinase (MMP) expression and activity, and tissue-specific gene expression. This induction was greater than that seen with IL-1β application to the chondral component directly, indicative of active biochemical communication between the two tissue layers and supporting the osteochondral nature of OA. The microtissue culture system developed here offers novel capabilities for investigating the physiology of osteochondral tissue and pathogenic mechanisms of OA and serving as a high-throughput platform to test potential

  3. Scaffold- and Cell System-Based Bone Grafts in Tissue Engineering (Review

    Directory of Open Access Journals (Sweden)

    Kuznetsova D.S.

    2014-12-01

    Full Text Available The review considers the current trends in tissue engineering including maxillofacial surgery based on the use of scaffolds, autologous stem cells and bioactive substances. The authors have shown the advantages and disadvantages of basic materials used for scaffold synthesis — three-dimensional porous or fiber matrices serving as a mechanical frame for cells; among such materials there are natural polymers (collagen, cellulose, fibronectin, chitosan, alginate and agarose, fibroin, synthetic polymers (polylactide, polyglycolide, polycaprolactone, polyvinyl alcohol and bioceramics (hydroxyapatite, tricalcium phosphate and bioactive glasses. There have been demonstrated the matrix techniques, special attention being paid to innovative technologies of rapid prototyping — the process of 3D-imaging according to a digital model. The most applicable of these techniques for biopolymers are laser stereolithography, selective laser sintering, fused deposition modeling, and 3D-printing. Great emphasis has been put on the use of bioactive substances in the process of obtaining scaffold-based bioengineered constructions — setting of stem cells on matrices before their transplantation to the defect area. Special attention has been given to a current trend of cellular biology — the application of multipotent mesenchymal stromal cells (most common marrow cells used in bone tissue regeneration, in particular, the available sources of their isolation and the variants of directed osteogenic differentiation have been presented. The review covers the characteristics and aims of bioactive substance inclusion in scaffold structure — not only to induce osteogenic differentiation, but also to attract new stem cells of a carrier, as well as promote angiogenesis.

  4. A magnetic nanoparticle-based multiple-gene delivery system for transfection of porcine kidney cells.

    Directory of Open Access Journals (Sweden)

    Yan Wang

    Full Text Available Superparamagnetic nanoparticles are promising candidates for gene delivery into mammalian somatic cells and may be useful for reproductive cloning using the somatic cell nuclear transfer technique. However, limited investigations of their potential applications in animal genetics and breeding, particularly multiple-gene delivery by magnetofection, have been performed. Here, we developed a stable, targetable and convenient system for delivering multiple genes into the nuclei of porcine somatic cells using magnetic Fe3O4 nanoparticles as gene carriers. After surface modification by polyethylenimine, the spherical magnetic Fe3O4 nanoparticles showed strong binding affinity for DNA plasmids expressing the genes encoding a green (DNAGFP or red (DNADsRed fluorescent protein. At weight ratios of DNAGFP or DNADsRed to magnetic nanoparticles lower than or equal to 10∶1 or 5∶1, respectively, the DNA molecules were completely bound by the magnetic nanoparticles. Atomic force microscopy analyses confirmed binding of the spherical magnetic nanoparticles to stretched DNA strands up to several hundred nanometers in length. As a result, stable and efficient co-expression of GFP and DsRed in porcine kidney PK-15 cells was achieved by magnetofection. The results presented here demonstrate the potential application of magnetic nanoparticles as an attractive delivery system for animal genetics and breeding studies.

  5. A CRISPR/Cas9-Based System for Reprogramming Cell Lineage Specification

    Directory of Open Access Journals (Sweden)

    Syandan Chakraborty

    2014-12-01

    Full Text Available Gene activation by the CRISPR/Cas9 system has the potential to enable new approaches to science and medicine, but the technology must be enhanced to robustly control cell behavior. We show that the fusion of two transactivation domains to Cas9 dramatically enhances gene activation to a level that is necessary to reprogram cell phenotype. Targeted activation of the endogenous Myod1 gene locus with this system led to stable and sustained reprogramming of mouse embryonic fibroblasts into skeletal myocytes. The levels of myogenic marker expression obtained by the activation of endogenous Myod1 gene were comparable to that achieved by overexpression of lentivirally delivered MYOD1 transcription factor.

  6. Advanced chemical hydride-based hydrogen generation/storage system for fuel cell vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Breault, R.W.; Rolfe, J. [Thermo Power Corp., Waltham, MA (United States)

    1998-08-01

    Because of the inherent advantages of high efficiency, environmental acceptability, and high modularity, fuel cells are potentially attractive power supplies. Worldwide concerns over clean environments have revitalized research efforts on developing fuel cell vehicles (FCV). As a result of intensive research efforts, most of the subsystem technology for FCV`s are currently well established. These include: high power density PEM fuel cells, control systems, thermal management technology, and secondary power sources for hybrid operation. For mobile applications, however, supply of hydrogen or fuel for fuel cell operation poses a significant logistic problem. To supply high purity hydrogen for FCV operation, Thermo Power`s Advanced Technology Group is developing an advanced hydrogen storage technology. In this approach, a metal hydride/organic slurry is used as the hydrogen carrier and storage media. At the point of use, high purity hydrogen will be produced by reacting the metal hydride/organic slurry with water. In addition, Thermo Power has conceived the paths for recovery and regeneration of the spent hydride (practically metal hydroxide). The fluid-like nature of the spent hydride/organic slurry will provide a unique opportunity for pumping, transporting, and storing these materials. The final product of the program will be a user-friendly and relatively high energy storage density hydrogen supply system for fuel cell operation. In addition, the spent hydride can relatively easily be collected at the pumping station and regenerated utilizing renewable sources, such as biomass, natural, or coal, at the central processing plants. Therefore, the entire process will be economically favorable and environmentally friendly.

  7. Establishment of a cell-based assay system for hepatitis C virus serine protease and its primary applications

    Institute of Scientific and Technical Information of China (English)

    Hong-Xia Mao; Shui-Yun Lan; Yun-Wen Hu; Li Xiang; Zheng-Hong Yuan

    2003-01-01

    AIM: To establish an efficient, sensitive, cell-based assay system for NS3 serine protease in an effort to study further the property of hepatitis C virus (HCV) and develop new antiviral agents.METHOOS: We constructed pCI-neo-NS3/4A-SEAP chimeric plasmid, in which the secreted alkaline phosphatase (SEAP) was fused in-frame to the downstream of NS4A/4B cleavage site. The protease activity of NS3 was reflected by the activity of SEAP in the culture media of transient or stable expression cells. Stably expressing cell lines were obtained by G418 selection. Pefabloc SC, a potent irreversible serine protease inhibitor, was used to treat the stably expressing cell lines to assess the system for screening NS3 inhibitors. To compare the activity of serine proteases from 1b and 1a, two chimeric clones were constructed and introduced into both transient and stable expression systems.RESULTS: The SEAP activity in the culture media could be detected in both transient and stable expression systems,and was apparently decreased after Pefabloc SC treatment.In both transient and stable systems, NS3/4A-SEAP chimeric gene from HCV genotype 1b produced higher SEAP activity in the culture media than that from 1a.CONCLUSION: The cell-based system is efficient and sensitive enough for detection and comparison of NS3 protease activity, and screening of anti-NS3 inhibitors. The functional difference between NS3/4A from 1a and 1b subtypes revealed by this system provides a clue for further investigations.

  8. Automaton based detection of affected cells in three dimensional biological system

    CERN Document Server

    Dundas, Jitesh

    2011-01-01

    The aim of this research review is to propose the logic and search mechanism for the development of an artificially intelligent automaton (AIA) that can find affected cells in a 3-dimensional biological system. Research on the possible application of such automatons to detect and control cancer cells in the human body are greatly focused MRI and PET scans finds the affected regions at the tissue level even as we can find the affected regions at the cellular level using the framework. The AIA may be designed to ensure optimum utilization as they record and might control the presence of affected cells in a human body. The proposed models and techniques can be generalized and used in any application where cells are injured or affected by some disease or accident. The best method to import AIA into the body without surgery or injection is to insert small pill like automata, carrying material viz drugs or leukocytes that is needed to correct the infection. In this process, the AIA can be compared to nano pills to ...

  9. The Multiscale Systems Immunology project: software for cell-based immunological simulation

    Directory of Open Access Journals (Sweden)

    Kepler Thomas B

    2008-04-01

    Full Text Available Abstract Background Computer simulations are of increasing importance in modeling biological phenomena. Their purpose is to predict behavior and guide future experiments. The aim of this project is to model the early immune response to vaccination by an agent based immune response simulation that incorporates realistic biophysics and intracellular dynamics, and which is sufficiently flexible to accurately model the multi-scale nature and complexity of the immune system, while maintaining the high performance critical to scientific computing. Results The Multiscale Systems Immunology (MSI simulation framework is an object-oriented, modular simulation framework written in C++ and Python. The software implements a modular design that allows for flexible configuration of components and initialization of parameters, thus allowing simulations to be run that model processes occurring over different temporal and spatial scales. Conclusion MSI addresses the need for a flexible and high-performing agent based model of the immune system.

  10. Functional study of p38 mitogen-activated protein kinase based on cell-penetrating peptide delivery system

    Institute of Scientific and Technical Information of China (English)

    Liping Yang; Yongming Yao; Zhiyong Sheng; Xiaomei Zhu; Yong Jiang

    2009-01-01

    Objective p38 Mitogen-activated protein kinase (MAPK) is a crossing center of various pathways. In this study, protein transduction system based on human immunodeficiency virus (HIV)-1 transactivator of transcription (TAT), which is an efficient delivery peptide of the foreign proteins into cells, was employed to study p38 MAPK functions in eukaryotic cells. Methods p38 And its dominant negative form, p38AF, were constructed into pET-His-TAT vector correctly to verify that the recombinant plasmids were well-founded through restriction enzyme digestion and DNA sequencing. The two proteins, His-TAT-p38 and His-TAT-p38AF, were expressed and purified in Escherichia coli by SDS-PAGE. Then they were incubated with ECV304 cells respectively and readily transduced into cells in a time-dependent and dose-dependent manner. The cells were stimulated by sorbitol. Activating transcription factor (ATF) 2 phosphorylation level was checked using Western blot to assess the activity of endogenous p38. Results Compared with controls, it was found that His-TAT-p38 increased the level ofATF2 phosphorylation in sorbitol-stimulated ECV304 cells, while His-TAT-p38AF inhibited it, indicating p38 MAPK protein delivery system based on TAT was constructed successfully. TAT-p38 and its dominant negative form possessed high biological activity after transduction into ECV304 cells by TAT protein delivery system. The results showed that p38AF fused with TAT could inhibit the transduction of endogenous p38 signal pathway in part, and other pathway might regulate p38 phosphorylation. Conclusions Our study provides a novel pathway to inhibit p38 signal pathway and establish a new method to study p38 function.

  11. Enzyme-based flow injection analysis system for glutamine and glutamate in mammalian cell culture media.

    Science.gov (United States)

    Mayer, C; Frauer, A; Schalkhammer, T; Pittner, F

    1999-03-01

    We present the setup of a flow injection analysis system designed for on-line monitoring of glutamate and glutamine. These amino acids represent a major energy source in mammalian cell culture. A cycling assay consisting of glutamate dehydrogenase and aspartate aminotransferase produces NADH proportional to the glutamate concentration in the sample. NADH is then measured spectrophotometrically. Glutamine is determined by conversion to glutamate which is fed into the cycling assay. The conversion of glutamine to glutamate is catalyzed by asparaginase. Asparaginase was used in place of glutaminase due to its relatively high reactivity with glutamine and a pH optimum similar to that of glutamate dehydrogenase. The enzymes were immobilized covalently to activated controlled pore glass beads and integrated into the flow injection analysis system. The application of the immobilized enzymes and the technical setup are presented in this paper.

  12. Desulfurization of jet fuel for fuel cell-based APU systems in aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Pasel, J.; Peters, R.; Stolten, D. [Forschungszentrum Juelich GmbH (Germany)

    2010-07-01

    To prevent the catalysts in fuel cell systems from poisoning by sulfur containing substances the fuel to be used must be desulfurized to a maximum of 10 ppmw of sulfur. Since the conventional hydrodesulfurization process employed in the refinery industry is not suitable for mobile fuel cell applications (e.g. auxiliary power units, APUs), the present study aims at developing an alternative process and determining its technical feasibility. A large number of processes were assessed with respect to their application in fuel cell APUs. The results revealed that a two-step process combining pervaporation and adsorption is a suitable process for the on-board desulfurization of jet fuel. The investigations to evaluate this process are presented in this paper. Seven different membrane materials and ten sorbent materials were screened to choose the most suitable candidates. Further laboratory experiments were conducted to optimize the operating conditions and to collect data for a pilot plant design. Different jet fuel qualities with up to 1650 ppmw of sulfur can be desulfurized to a level of 10 ppmw. (orig.)

  13. Polymer solar cells based on poly(3-hexylthiophene) and fullerene: Pyrene acceptor systems

    Energy Technology Data Exchange (ETDEWEB)

    Cominetti, Alessandra; Pellegrino, Andrea; Longo, Luca [Research Center for Renewable Energies and Environment, Istituto Donegani, Eni S.p.A, Via Fauser 4, IT-28100 Novara (Italy); Po, Riccardo, E-mail: riccardo.po@eni.com [Research Center for Renewable Energies and Environment, Istituto Donegani, Eni S.p.A, Via Fauser 4, IT-28100 Novara (Italy); Tacca, Alessandra; Carbonera, Chiara; Salvalaggio, Mario [Research Center for Renewable Energies and Environment, Istituto Donegani, Eni S.p.A, Via Fauser 4, IT-28100 Novara (Italy); Baldrighi, Michele; Meille, Stefano Valdo [Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, via Mancinelli 7, IT-20131 Milano (Italy)

    2015-06-01

    The replacement of widely used fullerene derivatives, e.g. [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), with unfunctionalized C60 and C70 is an effective approach to reduce the costs of organic photovoltaics. However, solubility issues of these compounds have always represented an obstacle to their use. In this study, bulk-heterojunction solar cells made of poly(3-hexylthiophene) donor polymer, C60 or C70 acceptors and a pyrene derivative (1-pyrenebutiric acid butyl ester) are reported. Butyl 1-pyrenebutirate limits the aggregation of fullerenes and improves the active layer morphology, plausibly due to the formation of pyrene-fullerene complexes which, in the case of pyrene-C70, were also obtained in a crystalline form. Maximum power conversion efficiencies of 1.54% and 2.50% have been obtained using, respectively, C60 or C70 as acceptor. Quantum mechanical modeling provides additional insight into the formation of plausible supermolecular structures via π-π interactions and on the redox behaviour of pyrene-fullerene systems. - Highlights: • Pyrene derivatives favour the dispersion of unfunctionalized fullerenes. • Polymer solar cells with pyrene: C60 adduct as acceptor have efficiencies of 1.54%. • When C60 is substituted with C70 the efficiency is increased to 2.50%. • DFT calculations support the plausibility of the formation of pyrene: fullerene adducts. • The use of unfunctionalized fullerenes may decrease the costs of polymer solar cells.

  14. Polymer solar cells based on poly(3-hexylthiophene) and fullerene: Pyrene acceptor systems

    International Nuclear Information System (INIS)

    The replacement of widely used fullerene derivatives, e.g. [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), with unfunctionalized C60 and C70 is an effective approach to reduce the costs of organic photovoltaics. However, solubility issues of these compounds have always represented an obstacle to their use. In this study, bulk-heterojunction solar cells made of poly(3-hexylthiophene) donor polymer, C60 or C70 acceptors and a pyrene derivative (1-pyrenebutiric acid butyl ester) are reported. Butyl 1-pyrenebutirate limits the aggregation of fullerenes and improves the active layer morphology, plausibly due to the formation of pyrene-fullerene complexes which, in the case of pyrene-C70, were also obtained in a crystalline form. Maximum power conversion efficiencies of 1.54% and 2.50% have been obtained using, respectively, C60 or C70 as acceptor. Quantum mechanical modeling provides additional insight into the formation of plausible supermolecular structures via π-π interactions and on the redox behaviour of pyrene-fullerene systems. - Highlights: • Pyrene derivatives favour the dispersion of unfunctionalized fullerenes. • Polymer solar cells with pyrene: C60 adduct as acceptor have efficiencies of 1.54%. • When C60 is substituted with C70 the efficiency is increased to 2.50%. • DFT calculations support the plausibility of the formation of pyrene: fullerene adducts. • The use of unfunctionalized fullerenes may decrease the costs of polymer solar cells

  15. Optimal Enactment of a Stand-alone Hybrid Wind-Fuel Cell based Distributed Generation System through Fuzzy Logic Control

    OpenAIRE

    Mohammad Saad Alam

    2014-01-01

    In this work, a hybrid distributed power generation (DG) system composed of two renewable energy sources, viz. a wind turbine and a fuel cell is proposed. A fuzzy logic controller has been introduced for optimal power management to provide electric supply to a residential load on a continuous basis based on the feasibility of economic power generation. This controller directs power to a fixed voltage bus in the power conditioning unit (PCU). The fixed voltage bus supplies the load, while the ...

  16. Systems biology approach to developing S2RM-based "systemstherapeutics" and naturally induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    The degree to, and the mechanisms through, whichstem cells are able to build, maintain, and heal the bodyhave only recently begun to be understood. Much of thestem cell's power resides in the release of a multitudeof molecules, called stem cell released molecules (SRM).A fundamentally new type of therapeutic, namely"systems therapeutic", can be realized by reverseengineering the mechanisms of the SRM processes.Recent data demonstrates that the composition of theSRM is different for each type of stem cell, as well asfor different states of each cell type. Although systemsbiology has been successfully used to analyze multiplepathways, the approach is often used to develop a smallmolecule interacting at only one pathway in the system.A new model is emerging in biology where systemsbiology is used to develop a new technology actingat multiple pathways called "systems therapeutics". Anatural set of healing pathways in the human that usesSRM is instructive and of practical use in developingsystems therapeutics. Endogenous SRM processes inthe human body use a combination of SRM from twoor more stem cell types, designated as S2RM, doing sounder various state dependent conditions for each celltype. Here we describe our approach in using statedependentSRM from two or more stem cell types,S2RM technology, to develop a new class of therapeuticscalled "systems therapeutics." Given the ubiquitous andpowerful nature of innate S2RM-based healing in thehuman body, this "systems therapeutic" approach usingS2RM technology will be important for the developmentof anti-cancer therapeutics, antimicrobials, woundcare products and procedures, and a number of othertherapeutics for many indications.

  17. Optimal Enactment of a Stand-alone Hybrid Wind-Fuel Cell based Distributed Generation System through Fuzzy Logic Control

    Directory of Open Access Journals (Sweden)

    Mohammad Saad Alam

    2014-01-01

    Full Text Available In this work, a hybrid distributed power generation (DG system composed of two renewable energy sources, viz. a wind turbine and a fuel cell is proposed. A fuzzy logic controller has been introduced for optimal power management to provide electric supply to a residential load on a continuous basis based on the feasibility of economic power generation. This controller directs power to a fixed voltage bus in the power conditioning unit (PCU. The fixed voltage bus supplies the load, while the excess power is directed to the energy storage bank first and then to an electrolyzer, which is used to generate hydrogen for the fuel cell. Complete system modeling and simulation has been carried out through HOMER software, and hybrid controller has been simulated in Simulink/MATLAB environment. The simulation results proved the effectiveness of the hybrid fuzzy logic controller for real-time applications of intelligent methods in sustainable power and energy systems.

  18. Hybrid electric system based on fuel cell and battery and integrating a single dc/dc converter for a tramway

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Luis M., E-mail: luis.fernandez@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Pablo, E-mail: pablo.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Carlos Andres, E-mail: carlosandres.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Jurado, Francisco, E-mail: fjurado@ujaen.e [Department of Electrical Engineering, EPS Linares, University of Jaen, C/Alfonso X, No. 28. 23700 Linares (Jaen) (Spain)

    2011-05-15

    Research highlights: {yields} Hybrid electric power system for a real surface tramway. {yields} Hybrid system based on PEM fuel cell with dc/dc converter and Ni-MH battery. {yields} New control strategy for the energy management of the tramway. {yields} Hybrid system demonstrated to meet appropriate driving cycle of the tramway. -- Abstract: This paper presents a hybrid electric power system for a real surface tramway. The hybrid system consists of two electrical energy sources integrating a single dc/dc converter to provide the power demanded by the tramway loads (four electric traction motors and auxiliary services): (1) a Polymer Electrolyte Membrane (PEM) fuel cell (FC) as the primary and (2) a rechargeable Ni-MH battery as electrical energy storage to supplement the FC over the driving cycle. According to the requirements of the real driving cycle of the tramway, it was considered a 200 kW PEM FC system with two FCs connected in parallel and a 34 Ah Ni-MH battery. The PEM FC and Ni-MH battery models were designed from commercially available components. The power conditioning system provides the appropriate power for the tramway. It is composed of: (1) a unique dc/dc boot converter which adapts the FC output voltage to the 750 V traction standard dc bus; (2) three phase inverters to drive properly each electric motors; and (3) a braking chopper to dissipate excess of regenerative braking energy. Suitable state machine control architecture is presented for the hybrid system, its objective being to provide demanded power by the driving cycle, optimizing the energy generated. Following this objective, a new state machine control strategy based on eight states decides the operating point of each component of the system and a cascade control structure allows achieving the operating points determined by the strategy. Simulation results of the real driving cycle of the tramway check the adequacy of the hybrid electric power system.

  19. A gas circulation and purification system for gas-cell-based low-energy RI-beam production

    Science.gov (United States)

    Sonoda, T.; Tsubota, T.; Wada, M.; Katayama, I.; Kojima, T. M.; Reponen, M.

    2016-06-01

    A gas circulation and purification system was developed at the RIKEN Radioactive Isotope Beam Factory that can be used for gas-cell-based low-energy RI-beam production. A high-flow-rate gas cell filled with one atmosphere of buffer gas (argon or helium) is used for the deceleration and thermalization of high-energy RI-beams. The exhausted buffer gas is efficiently collected using a compact dry pump and returned to the gas cell with a recovery efficiency of >97%. The buffer gas is efficiently purified using two gas purifiers as well as collision cleaning, which eliminates impurities in the gas. An impurity level of one part per billion is achieved with this method.

  20. On-line experimental results of an argon gas cell-based laser ion source (KEK Isotope Separation System)

    Science.gov (United States)

    Hirayama, Y.; Watanabe, Y. X.; Imai, N.; Ishiyama, H.; Jeong, S. C.; Jung, H. S.; Miyatake, H.; Oyaizu, M.; Kimura, S.; Mukai, M.; Kim, Y. H.; Sonoda, T.; Wada, M.; Huyse, M.; Kudryavtsev, Yu.; Van Duppen, P.

    2016-06-01

    KEK Isotope Separation System (KISS) has been developed at RIKEN to produce neutron rich isotopes with N = 126 to study the β -decay properties for application to astrophysics. The KISS is an element-selective mass-separation system which consists of an argon gas cell-based on laser ion source for atomic number selection and an ISOL mass-separation system. The argon gas cell of KISS is a key component to stop and collect the unstable nuclei produced in a multi-nucleon transfer reaction, where the isotopes of interest will be selectively ionized using laser resonance ionization. We have performed off- and on-line experiments to study the basic properties of the gas cell as well as of the KISS. We successfully extracted the laser-ionized stable 56Fe (direct implantation of a 56Fe beam into the gas cell) atoms and 198Pt (emitted from the 198Pt target by elastic scattering with a 136Xe beam) atoms from the KISS during the commissioning on-line experiments. We furthermore extracted laser-ionized unstable 199Pt atoms and confirmed that the measured half-life was in good agreement with the reported value.

  1. The modeling and simulation of thermal based modified solid oxide fuel cell (SOFC for grid-connected systems

    Directory of Open Access Journals (Sweden)

    Ayetül Gelen

    2015-05-01

    Full Text Available This paper presents a thermal based modified dynamic model of a Solid Oxide Fuel Cell (SOFC for grid-connected systems. The proposed fuel cell model involves ohmic, activation and concentration voltage losses, thermal dynamics, methanol reformer, fuel utilization factor and power limiting module. A power conditioning unit (PCU, which consists of a DC-DC boost converter and a DC-AC voltage-source inverter (VSI, their controller, transformer and filter, is designed for grid-connected systems. The voltage-source inverter with six Insulated Gate Bipolar Transistor (IGBT switches inverts the DC voltage that comes from the converter into a sinusoidal voltage synchronized with the grid. The simulations and modeling of the system are developed on Matlab/Simulink environment. The performance of SOFC with converter is examined under step and random load conditions. The simulation results show that the designed boost converter for the proposed thermal based modified SOFC model has fairly followed different DC load variations. Finally, the AC bus of 400 Volt and 50 Hz is connected to a single-machine infinite bus (SMIB through a transmission line. The real and reactive power managements of the inverter are analyzed by an infinite bus system. Thus, the desired nominal values are properly obtained by means of the inverter controller.

  2. Implementing oxygen control in chip-based cell and tissue culture systems

    NARCIS (Netherlands)

    Oomen, Pieter; Skolimowski, Maciej; Verpoorte, Elisabeth

    2016-01-01

    Oxygen is essential in the energy metabolism of cells, as well as being an important regulatory parameter influencing cell differentiation and function. Interest in precise oxygen control for in vitro cultures of tissues and cells continues to grow, especially with the emergence of the organ-on-a-ch

  3. A vector-based system for the differentiation of mouse embryonic stem cells toward germ-line cells

    Directory of Open Access Journals (Sweden)

    Reza Ebrahimzadeh-Vesal

    2014-08-01

    Conclusion: In this study, we demonstrated the in vitro generation of mouse embryonic stem cells to germ cells by using a backbone vector containing the fusion gene Stra8-EGFP. The Stra8 gene is a retinoic acid-responsive protein and is able to regulate meiotic initiation.

  4. Intelligent CAD System for Automatic Detection of Mitotic Cells from Breast Cancer Histology Slide Images Based on Teaching-Learning-Based Optimization

    Directory of Open Access Journals (Sweden)

    Ramin Nateghi

    2014-01-01

    Full Text Available This paper introduces a computer-assisted diagnosis (CAD system for automatic mitosis detection from breast cancer histopathology slide images. In this system, a new approach for reducing the number of false positives is proposed based on Teaching-Learning-Based optimization (TLBO. The proposed CAD system is implemented on the histopathology slide images acquired by Aperio XT scanner (scanner A. In TLBO algorithm, the number of false positives (falsely detected nonmitosis candidates as mitosis ones is defined as a cost function and, by minimizing it, many of nonmitosis candidates will be removed. Then some color and texture (textural features such as those derived from cooccurrence and run-length matrices are extracted from the remaining candidates and finally mitotic cells are classified using a specific support vector machine (SVM classifier. The simulation results have proven the claims about the high performance and efficiency of the proposed CAD system.

  5. On-line experimental validation of a model-based diagnostic algorithm dedicated to a solid oxide fuel cell system

    Science.gov (United States)

    Polverino, Pierpaolo; Esposito, Angelo; Pianese, Cesare; Ludwig, Bastian; Iwanschitz, Boris; Mai, Andreas

    2016-02-01

    In the current energetic scenario, Solid Oxide Fuel Cells (SOFCs) exhibit appealing features which make them suitable for environmental-friendly power production, especially for stationary applications. An example is represented by micro-combined heat and power (μ-CHP) generation units based on SOFC stacks, which are able to produce electric and thermal power with high efficiency and low pollutant and greenhouse gases emissions. However, the main limitations to their diffusion into the mass market consist in high maintenance and production costs and short lifetime. To improve these aspects, the current research activity focuses on the development of robust and generalizable diagnostic techniques, aimed at detecting and isolating faults within the entire system (i.e. SOFC stack and balance of plant). Coupled with appropriate recovery strategies, diagnosis can prevent undesired system shutdowns during faulty conditions, with consequent lifetime increase and maintenance costs reduction. This paper deals with the on-line experimental validation of a model-based diagnostic algorithm applied to a pre-commercial SOFC system. The proposed algorithm exploits a Fault Signature Matrix based on a Fault Tree Analysis and improved through fault simulations. The algorithm is characterized on the considered system and it is validated by means of experimental induction of faulty states in controlled conditions.

  6. Untargeted Proteomics and Systems-Based Mechanistic Investigation of Artesunate in Human Bronchial Epithelial Cells.

    Science.gov (United States)

    Ravindra, Kodihalli C; Ho, Wanxing Eugene; Cheng, Chang; Godoy, Luiz C; Wishnok, John S; Ong, Choon Nam; Wong, W S Fred; Wogan, Gerald N; Tannenbaum, Steven R

    2015-10-19

    The antimalarial drug artesunate is a semisynthetic derivative of artemisinin, the principal active component of a medicinal plant Artemisia annua. It is hypothesized to attenuate allergic asthma via inhibition of multiple signaling pathways. We used a comprehensive approach to elucidate the mechanism of action of artesunate by designing a novel biotinylated dihydroartemisinin (BDHA) to identify cellular protein targets of this anti-inflammatory drug. By adopting an untargeted proteomics approach, we demonstrated that artesunate may exert its protective anti-inflammatory effects via direct interaction with multiple proteins, most importantly with a number of mitochondrial enzymes related to glucose and energy metabolism, along with mRNA and gene expression, ribosomal regulation, stress responses, and structural proteins. In addition, the modulatory effects of artesunate on various cellular transcription factors were investigated using a transcription factor array, which revealed that artesunate can simultaneously modulate multiple nuclear transcription factors related to several major pro- and anti-inflammatory signaling cascades in human bronchial epithelial cells. Artesunate significantly enhanced nuclear levels of nuclear factor erythroid-2-related factor 2 (Nrf2), a key promoter of antioxidant mechanisms, which is inhibited by the Kelch-like ECH-associated protein 1 (Keap1). Our results demonstrate that, like other electrophilic Nrf2 regulators, artesunate activates this system via direct molecular interaction/modification of Keap1, freeing Nrf2 for transcriptional activity. Altogether, the molecular interactions and modulation of nuclear transcription factors provide invaluable insights into the broad pharmacological actions of artesunate in inflammatory lung diseases and related inflammatory disorders. PMID:26340163

  7. Alginate based hydrogel as a potential biopolymeric carrier for drug delivery and cell delivery systems: present status and applications.

    Science.gov (United States)

    Giri, Tapan Kumar; Thakur, Deepa; Alexander, Amit; Ajazuddin; Badwaik, Hemant; Tripathi, Dulal Krishna

    2012-11-01

    Alginate is a non-toxic, biocompatible and biodegradable natural polymer with a number of peculiar physicochemical properties for which it has wide applications in drug delivery and cell delivery systems. Hydrogel formation can be obtained by interactions of anionic alginates with multivalent inorganic cations by simple ionotropic gelation method. Hydrophilic polymeric network of three dimensional cross linked structures of hydrogels absorb substantial amount of water or biological fluids. Among the numerous biomaterials used for hydrogel formation alginate has been and will continue to be one of the most important biomaterial. Therefore, in view of the vast literature support, we focus in this review on alginate - based hydrogel as drug delivery and cell delivery carriers for biomedical applications. Various properties of alginates, their hydrogels and also various techniques used for preparing alginate hydrogels have been reviewed. PMID:22998675

  8. A quasi-direct methanol fuel cell system based on blend polymer membrane electrolytes

    DEFF Research Database (Denmark)

    Li, Qingfeng; Hjuler, Hans Aage; Hasiotis, C.;

    2002-01-01

    On the basis of blend polymer electrolytes of polybenzimidazole and sulfonated polysulfone, a polymer electrolyte membrane fuel cell was developed with an operational temperature up to 200degrees C. Due to the high operational temperature, the fuel cell can tolerate 1.0-3.0 vol % CO in the fuel...

  9. Analysis of DC/DC Converter Efficiency for Energy Storage System Based on Bidirectional Fuel Cells

    DEFF Research Database (Denmark)

    Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.

    2013-01-01

    Renewable energy sources are fluctuating depending on the availability of the energy source. For this reason, energy storage is becoming more important and bidirectional fuel cells represent an attractive technology. Fuel cells require highcurrent low-voltage dc-dc or dc-ac converters as power in...

  10. Microelectromechanical System-Based Sensing Arrays for Comparative in Vitro Nanotoxicity Assessment at Single Cell and Small Cell-Population Using Electrochemical Impedance Spectroscopy.

    Science.gov (United States)

    Shah, Pratikkumar; Zhu, Xuena; Zhang, Xueji; He, Jin; Li, Chen-zhong

    2016-03-01

    The traditional in vitro nanotoxicity assessment approaches are conducted on a monolayer of cell culture. However, to study a cell response without interference from the neighbor cells, a single cell study is necessary; especially in cases of neuronal, cancerous, and stem cells, wherein an individual cell's fate is often not explained by the whole cell population. Nonetheless, a single cell does not mimic the actual in vivo environment and lacks important information regarding cell communication with its microenvironment. Both a single cell and a cell population provide important and complementary information about cells' behaviors. In this research, we explored nanotoxicity assessment on a single cell and a small cell population using electrochemical impedance spectroscopy and a microelectromechanical system (MEMS) device. We demonstrated a controlled capture of PC12 cells in different-sized microwells (to capture a different number of cells) using a combined method of surface functionalization and dielectrophoresis. The present approach provides a rapid nanotoxicity response as compared to other conventional approaches. This is the first study, to our knowledge, which demonstrates a comparative response of a single cell and small cell colonies on the same MEMS platform, when exposed to metaloxide nanoparticles. We demonstrated that the microenvironment of a cell is also accountable for cells' behaviors and their responses to nanomaterials. The results of this experimental study open up a new hypothesis to be tested for identifying the role of cell communication in spreading toxicity in a cell population.

  11. Development and characterization of a green fluorescent protein-based rat cell bioassay system for detection of AH receptor ligands

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Bin; Denison, M. [California Univ., Davis, CA (United States). Dept. of Environmental Toxicology

    2004-09-15

    Proper epidemiological, risk assessment and exposure analysis of TCDD and related HAHs requires accurate measurements of these chemicals both in the species of interest and in various exposure matrices (i.e. biological, environmental, food and feed). While high-resolution instrumental analysis techniques are established for these chemicals, these procedures are very costly, time-consuming and are impractical for large scale sampling studies. Accordingly, numerous bioanalytical methods have been developed for the detection of these chemicals in extracts from a variety of matrices, the majority of which take the advantage of the ability of these chemicals to activate one or more aspects of the AhR-dependent mechanism of action. One of the most sensitive bioassay systems developed to date is the so-called CALUX (Chemically Activated Luciferase Expression) assay, which is based on novel recombinant cell lines that contain a stably transfected dioxin (AhR)-responsive firefly luciferase gene. Treatment of these cells with TCDD and related HAHs and polycyclic aromatic hydrocarbons (PAHs), as well as other AhR ligands, results in induction of reporter gene expression in a time-, dose-, AhR-, and chemical-specific manner. The level of reporter gene expression correlates with the total concentration of the TCDD-like AhR inducers (agonists) present in the sample. Although the firefly luciferase reporter gene contributes to the high degree of sensitivity of the assay, it also has limitations with respect to our need for a rapid and inexpensive bioassay for high-throughput screening analysis. Accordingly, we previously developed a stably transfected murine cell line containing an AhRresponsive enhanced green fluorescent protein (EGFP) reporter gene. This cell line provided us with a high-throughput cell bioassay system for identification and characterization of AhR agonists and antagonists. Here we have extended these studies and describe the development, optimization, and

  12. Systems cell biology.

    Science.gov (United States)

    Mast, Fred D; Ratushny, Alexander V; Aitchison, John D

    2014-09-15

    Systems cell biology melds high-throughput experimentation with quantitative analysis and modeling to understand many critical processes that contribute to cellular organization and dynamics. Recently, there have been several advances in technology and in the application of modeling approaches that enable the exploration of the dynamic properties of cells. Merging technology and computation offers an opportunity to objectively address unsolved cellular mechanisms, and has revealed emergent properties and helped to gain a more comprehensive and fundamental understanding of cell biology.

  13. Solar cell concentrating system

    International Nuclear Information System (INIS)

    This study reviews fabrication techniques and testing facilities for different solar cells under concentration which have been developed and tested. It is also aimed to examine solar energy concentrators which are prospective candidates for photovoltaic concentrator systems. This may provide an impetus to the scientists working in the area of solar cell technology

  14. Microcarrier-based platforms for in vitro expansion and differentiation of human pluripotent stem cells in bioreactor culture systems.

    Science.gov (United States)

    Badenes, Sara M; Fernandes, Tiago G; Rodrigues, Carlos A V; Diogo, Maria Margarida; Cabral, Joaquim M S

    2016-09-20

    Human pluripotent stem cells (hPSC) have attracted a great attention as an unlimited source of cells for cell therapies and other in vitro biomedical applications such as drug screening, toxicology assays and disease modeling. The implementation of scalable culture platforms for the large-scale production of hPSC and their derivatives is mandatory to fulfill the requirement of obtaining large numbers of cells for these applications. Microcarrier technology has been emerging as an effective approach for the large scale ex vivo hPSC expansion and differentiation. This review presents recent achievements in hPSC microcarrier-based culture systems and discusses the crucial aspects that influence the performance of these culture platforms. Recent progress includes addressing chemically-defined culture conditions for manufacturing of hPSC and their derivatives, with the development of xeno-free media and microcarrier coatings to meet good manufacturing practice (GMP) quality requirements. Finally, examples of integrated platforms including hPSC expansion and directed differentiation to specific lineages are also presented in this review. PMID:27480342

  15. On Orbit Immuno-Based, Label-Free, White Blood Cell Counting System with MicroElectroMechanical Sensor (MEMS) Technology (OILWBCS-MEMS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aurora Flight Sciences Corporation and partner, Draper Laboratory, propose to develop an on-orbit immuno-based label-free white blood cell counting system using...

  16. On Orbit Immuno-Based, Label-Free, White Blood Cell Counting System with MicroElectroMechanical Sensor (MEMS) Technology (OILWBCS-MEMS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aurora Flight Sciences Corporation and our partner, Draper Laboratory, propose to develop an on orbit immuno-based, label-free, white blood cell counting system for...

  17. Exergetic and exergoeconomic evaluation of a solid-oxide fuel-cell-based combined heat and power generation system

    International Nuclear Information System (INIS)

    Highlights: • Exergy-based evaluations of a SOFC-based power generation system have been made. • The exergy of fuel and the exergy of product are rigorously defined. • Cost balance and auxiliary equations are formulated for the exergoeconomic analysis. • The cost structure of the overall system has been analyzed. • Suggestions are made for improving the cost effectiveness of the entire system. - Abstract: Exergetic and exergoeconomic evaluations have been carried out for a 100 kW-class solid-oxide fuel-cell-based combined heat and power generation system, to find out the measures that would improve its efficiency, and, more importantly, its cost effectiveness. The exergoeconomic analysis is an appropriate combination of an exergetic analysis and an economic analysis; through exergoeconomics, we obtain the real cost associated with each stream and with the inefficiencies within each component in a system. For the analyses, the exergies of fuel and the exergies of product for all components have been defined. Subsequently, the exergetic efficiency of each component has been evaluated. By combining the results obtained from an economic analysis with the results of the exergetic analysis, the cost structure of the overall system has been figured out. The components, showing higher exergoeconomic factors such as SOFC stack, fuel blower, heat recovery water pump, and inverter, need reduction of investment cost, even if the associated efficiency would decreased because of this cost reduction. For the components, exhibiting lower exergoeconomic factors such as integrated reformer, fuel/water pre-heater, and air pre-heater, the main focus should be on efficiency improvements, even if higher investment expenditures would be associated with such improvements

  18. Cell Maintenance Systems

    Science.gov (United States)

    Morrison, D. R.

    1985-01-01

    Living human cells require attachment to a suitable surface and special culture conditions in order to grow. These requirements are modified and amplified when cells are taken into a weightless environment. Special handling and maintenance systems are required for routine laboratory procedures conducted in the Orbiter and in the Spacelab. Methods were developed to maintain cells in special incubators designed for the Orbiter middeck, however, electrophoresis and other experiments require cells to be harvested off of the culture substrate before they can be processed or used. The cell transport assembly (CTA) was flown on STS-8, and results show that improvements are required to maintain adequate numbers of cells in this device longer than 48 hours. The life sciences middeck centrifuge probably can be used, but modifications will be required to transfer cells from the CTA and keep the cells sterile. Automated systems such as the Skylab SO-15 flight hardware and crew operated systems are being evaluated for use on the Space Shuttle, Spacelab, and Space Station research modules.

  19. An investigation of a carbon dioxide-based fuel cell system as a power generation alternative for Mars exploration applications

    Science.gov (United States)

    Salinas Mejia, Oscar Roberto

    The possibility of using a bifunctional carbon dioxide-based fuel cell system as the core of a propulsion system for a Mars exploration rotorcraft is investigated here. This concept involves the production of electricity by a stack of fuel cells that rely on carbon monoxide as the fuel and oxygen as the oxidizer. These two reactants are harvested from the Martian atmosphere by employing the same stack of cells as an electrolyzing unit. The general objectives of this research are to: prove the feasibility of the concept, produce a comprehensive model that allows the prediction of performance, and offer recommendations for the successful implementation of the concept. In this work, it is pointed out and demonstrated that, at least in theory, the overall electrochemical reaction required by this concept can be achieved by transporting hydrogen protons, hydroxyl radicals, carbonate radicals, or oxygen ions between the electrodes. Complete sets of reactions are prescribed for different types of fuel cells. Anodic and cathodic reactions are presented for acid, alkaline, carbonate, and solid oxide electrolytes. Subsequently, a more detailed consideration of all relevant phenomena is done by coupling elements of chemical kinetics, electrodics, electrochemistry, and thermodynamics with experimental data, to complete the demonstration of the feasibility of the carbon dioxide-based bifunctional fuel cell system. The understanding and inclusion of key processes and mechanisms allows the construction of a model that predicts the performance of the power generation subsystem advocated here. The model adopted in this work couples mechanistics with elements derived from the application of linear regression modeling techniques. Mechanistics are used to determine: thermodynamic equilibrium potential, overvoltages due to activation, ohmic resistance, and mass transport. This approach is empirical in part because the numerical parametric expressions suggested here have to be precised

  20. GRID-INDEPENDENT ELECTRICITY GENERATION FOR REMOTE AREAS BASED ON A UNITIZED HYDROXIDE EXCHANGE MEMBRANE FUEL CELL SYSTEM

    Science.gov (United States)

    The featured HEM has been previously demonstrated to be efficient in a hydrogen fuel cell. We intend to demonstrate the capability of this HEM to be used in an electrolyzer and integrate the system into a unitized regenerative fuel cell system. Solar photovoltaic energy will b...

  1. Direct Methanol Fuel Cell systems in portable electronics - a metrics-based conceptualization approach

    NARCIS (Netherlands)

    Flipsen, S.F.J.

    2010-01-01

    It is impossible to imagine life without portable electronics like the laptop computer and cell phone. All these products are powered by a battery, granting them grid independence and all-round protability. Connectivity to the internet and an increase of functionality demands for a better battery. T

  2. Inducing enhanced immunogenic cell death with nanocarrier-based drug delivery systems for pancreatic cancer therapy.

    Science.gov (United States)

    Zhao, Xiao; Yang, Keni; Zhao, Ruifang; Ji, Tianjiao; Wang, Xiuchao; Yang, Xiao; Zhang, Yinlong; Cheng, Keman; Liu, Shaoli; Hao, Jihui; Ren, He; Leong, Kam W; Nie, Guangjun

    2016-09-01

    Immunogenic cell death (ICD) occurs when apoptotic tumor cell elicits a specific immune response, which may trigger an anti-tumor effect, via the release of immunostimulatory damage-associated molecular patterns (DAMPs). Hypothesizing that nanomedicines may impact ICD due to their proven advantages in delivery of chemotherapeutics, we encapsulated oxaliplatin (OXA) or gemcitabine (GEM), an ICD and a non-ICD inducer respectively, into the amphiphilic diblock copolymer nanoparticles. Neither GEM nor nanoparticle-encapsulated GEM (NP-GEM) induced ICD, while both OXA and nanoparticle-encapsulated OXA (NP-OXA) induced ICD. Interestingly, NP-OXA treated tumor cells released more DAMPs and induced stronger immune responses of dendritic cells and T lymphocytes than OXA treatment in vitro. Furthermore, OXA and NP-OXA exhibited stronger therapeutic effects in immunocompetent mice than in immunodeficient mice, and the enhancement of therapeutic efficacy was significantly higher in the NP-OXA group than the OXA group. Moreover, NP-OXA treatment induced a higher proportion of tumor infiltrating activated cytotoxic T-lymphocytes than OXA treatment. This general trend of enhanced ICD by nanoparticle delivery was corroborated in evaluating another pair of ICD inducer and non-ICD inducer, doxorubicin and 5-fluorouracil. In conclusion, although nanoparticle encapsulation did not endow a non-ICD inducer with ICD-mediated anti-tumor capacity, treatment with a nanoparticle-encapsulated ICD inducer led to significantly enhanced ICD and consequently improved anti-tumor effects than the free ICD inducer. The proposed nanomedicine approach may impact cancer immunotherapy via the novel cell death mechanism of ICD. PMID:27343466

  3. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    Science.gov (United States)

    Benaouadj, M.; Aboubou, A.; Ayad, M. Y.; Bahri, M.; Boucetta, A.

    2016-07-01

    In this work, an optimal control (under constraints) based on the Pontryagin's maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: - Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, - Keep fuel cells working at optimal power delivery conditions, - Maintain constant voltage across the common DC bus, - Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control.Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  4. Toward Coordinated Robust Allocation of Reserve Policies for a Cell-based Power System

    DEFF Research Database (Denmark)

    Hu, Junjie; Heussen, Kai; Claessens, Bert;

    2016-01-01

    Conventional regulation reserves have fixed participation factors and are thus not well suited to utilize differentiated capabilities of ancillary service providers. This study applies linear decision rules-based (LDR) control policies, which effectively adapt the present participation factor...

  5. In situ monitoring of atmospheric nitrous acid based on multi-pumping flow system and liquid waveguide capillary cell.

    Science.gov (United States)

    Liu, Yuhan; Lu, Keding; Dong, Huabin; Li, Xin; Cheng, Peng; Zou, Qi; Wu, Yusheng; Liu, Xingang; Zhang, Yuanhang

    2016-05-01

    In the last four decades, various techniques including spectroscopic, wet chemical and mass spectrometric methods, have been developed and applied for the detection of ambient nitrous acid (HONO). We developed a HONO detection system based on long path photometry which consists of three independent modules i.e., sampling module, fluid propulsion module and detection module. In the propulsion module, solenoid pumps are applied. With solenoid pumps the pulsed flow can be computer controlled both in terms of pump stroke volume and pulse frequency, which enables the attainment of a very stable flow rate. In the detection module, a customized Liquid Waveguide Capillary Cell (LWCC) is used. The customized LWCC pre-sets the optical fiber in-coupling with the liquid wave guide, providing the option of fast startup and easy maintenance of the absorption photometry. In summer 2014, our system was deployed in a comprehensive campaign at a rural site in the North China Plain. More than one month of high quality HONO data spanning from the limit of detection to 5ppb were collected. Intercomparison of our system with another established system from Forschungszentrum Juelich is presented and discussed. In conclusion, our instrument achieved a detection limit of 10pptV within 2min and a measurement uncertainty of 7%, which is well suited for investigation of the HONO budget from urban to rural conditions in China. PMID:27155434

  6. Design of MPPT Based Hybrid Wind and Fuel - Cell Energy System

    Directory of Open Access Journals (Sweden)

    Ch Rambabu

    2011-12-01

    Full Text Available The wind energy conversion system can deliver the maximum power when the load impedance matches with the source impedance under a given wind speed. Since the load and wind speed are varying dynamically, the maximum power point tracking (MPPT becomes more complex. A wind-generator (WG maximum-power-point tracking (MPPT system is presented in the present work, consisting of a high efficiency buck-type dc/dc converter and a control unit running the MPPT functions. The advantages of the MPPT method are that no knowledge of the WG optimal power characteristic or measurement of the wind speed is required and the WG operates at a variable speed. Thus, the system features higher reliability, lower complexity and less mechanical stress of the WG. A hybrid algorithm is used for tracking the maximum power. In this method, on power variation, the duty cycle is adjusted in according to the variation in rectifier output voltage

  7. A validated system for ligation-free USER™ -based assembly of expression vectors for mammalian cell engineering

    DEFF Research Database (Denmark)

    Lund, Anne Mathilde; Kildegaard, Helene Faustrup; Hansen, Bjarne Gram;

    The development in the field of mammalian cell factories require fast and high-throughput methods, this means a high need for simpler and more efficient cloning techniques. For optimization of protein expression by genetic engineering and for allowing metabolic engineering in mammalian cells, a new...... versatile expression vector system was developed. This vector system applies the ligation-free uracilexcision cloning technique to construct mammalian expression vectors of multiple parts and with maximum flexibility....

  8. Review on the Recent Developments of Photovoltaic Thermal (PV/T and Proton Exchange Membrane Fuel Cell (PEMFC Based Hybrid System

    Directory of Open Access Journals (Sweden)

    Zulkepli Afzam

    2016-01-01

    Full Text Available Photovoltaic Thermal (PV/T system emerged as one of the convenient type of renewable energy system acquire the ability to generate power and thermal energy in the absence of moving parts. However, the power output of PV/T is intermittent due to dependency on solar irradiation condition. Furthermore, its efficiency decreases because of cells instability at high temperature. On the other hand, fuel cell co-generation system (CGS is another technology that can generate power and heat simultaneously. Integration of PV/T and fuel cell CGS could enhance the reliability and sustainability of both systems as well as increasing the overall system performance. Hence, this paper intended to present the parameters that affect performance of PV/T and Proton Exchange Membrane Fuel Cell (PEMFC CGS. Moreover, recent developments on PV/T-fuel cell hybrid system are also presented. Based on literates, mass flow rate of moving fluid in PV/T was found to affect the system efficiency. For the PEMFC, when the heat is utilized, the system performance can be increased where the heat efficiency is similar to electrical efficiency which is about 50%. Recent developments of hybrid PV/T and fuel cell show that most of the studies only focus on the power generation of the system. There are less study on the both power and heat utilization which is indeed necessary in future development in term of operation strategy, optimization of size, and operation algorithm.

  9. Impedance sensor technology for cell-based assays in the framework of a high-content screening system

    International Nuclear Information System (INIS)

    Living cultured cells react to external influences, such as pharmaceutical agents, in an intricate manner due to their complex internal signal processing. Impedance sensing of cells on microelectrodes is a favored label-free technology to indicate cellular events, usually ascribed to morphologic alteration or changes in cellular adhesion, which is usually found in stand-alone systems that do not incorporate life support or additional sensor systems. However, only in symbiosis with metabolic activity sensing and picture documentation may a complete insight into cellular vitality be provided. This complement was created within the framework of an automated high-content screening system previously developed by our group, monitoring 24 cell culture chambers in parallel. The objective of this paper is the development of miniaturized electronics for impedance measurements and its system integration as a modular unit. In addition, it is shown how sensor electrodes were optimized by impedance matching such that spectroscopy and raw data analysis become feasible for every culture well. Undesired mechanical stress on cultured cells may arise from the medium and agent support system of the autonomous screening apparatus. This paper demonstrates how this hazard is treated with the simulation of microfluidics and impedance measurements. Physiological data are subsequently derived from the exemplary tumor cell line MCF-7 both during treatment with the agent doxorubicin and through the impact of natural killer cells. This correlates the information content of complex impedance spectra with cellular respiration as well as data from microscopy

  10. Performance of a microbial fuel cell-based biosensor for online monitoring in an integrated system combining microbial fuel cell and upflow anaerobic sludge bed reactor.

    Science.gov (United States)

    Jia, Hui; Yang, Guang; Wang, Jie; Ngo, Huu Hao; Guo, Wenshan; Zhang, Hongwei; Zhang, Xinbo

    2016-10-01

    A hybrid system integrating a microbial fuel cell (MFC)-based biosensor with upflow anaerobic sludge blanket (UASB) was investigated for real-time online monitoring of the internal operation of the UASB reactor. The features concerned were its rapidity and steadiness with a constant operation condition. In addition, the signal feedback mechanism was examined by the relationship between voltage and time point of changed COD concentration. The sensitivity of different concentrations was explored by comparing the signal feedback time point between the voltage and pH. Results showed that the electrical signal feedback was more sensitive than pH and the thresholds of sensitivity were S=3×10(-5)V/(mg/L) and S=8×10(-5)V/(mg/L) in different concentration ranges, respectively. Although only 0.94% of the influent COD was translated into electricity and applied for biosensing, this integrated system indicated great potential without additional COD consumption for real-time monitoring. PMID:27372008

  11. A novel poly(propylene-co-imidazole) based biofuel cell: System optimization and operation for energy generation

    Energy Technology Data Exchange (ETDEWEB)

    Kilic, Muhammet Samet [Department of Chemistry, Bulent Ecevit University, 67100 Zonguldak (Turkey); Korkut, Seyda, E-mail: s.korkut@beun.edu.tr [Department of Environmental Engineering, Bulent Ecevit University, 67100 Zonguldak (Turkey); Hazer, Baki [Department of Chemistry, Bulent Ecevit University, 67100 Zonguldak (Turkey)

    2015-02-01

    This study describes the construction of an enzymatic fuel cell comprised of novel gold nanoparticles embedded poly(propylene-co-imidazole) coated anode and cathode. Working electrode fabrication steps and operational conditions for the fuel cell have been optimized to get enhanced power output. Electrical generation capacity of the optimized cell was tested by using the municipal wastewater sample. The enzymatic fuel cell system reached to maximum power density with 1 μg and 8 μg of polymer quantity and bilirubin oxidase on electrode surface, respectively. The maximum power output was calculated to be 5 μW cm{sup −2} at + 0.56 V (vs. Ag/AgCl) in phosphate buffer (pH 7.4, 100 mM, 20 °C) by the addition of 15 mM of glucose as a fuel source. The optimized enzymatic fuel cell generated a power density of 0.46 μW cm{sup −2} for the municipal wastewater sample. Poly(propylene-co-imidazole) was easily used for a fuel cell system owing to its metallic nanoparticle content. The developed fuel cell will play a significant role for energy conversion by using glucose readily found in wastewater and in vivo mediums. - Highlights: • Gold nanoparticles provided faster electron transfer in the circuit. • The maximum power density of 5 μW cm{sup −2} was generated at + 0.56 V cell potential. • The cell can be easily operated for in vivo mediums.

  12. In-cell protease assay systems based on trans-localizing molecular beacon proteins using HCV protease as a model system.

    Directory of Open Access Journals (Sweden)

    Jeong Hee Kim

    Full Text Available This study describes a sensitive in-cell protease detection system that enables direct fluorescence detection of a target protease and its inhibition inside living cells. This live-cell imaging system provides a fluorescent molecular beacon protein comprised of an intracellular translocation signal sequence, a protease-specific cleavage sequence, and a fluorescent tag sequence(s. The molecular beacon protein is designed to change its intracellular localization upon cleavage by a target protease, i.e., from the cytosol to a subcellular organelle or from a subcellular organelle to the cytosol. Protease activity can be monitored at the single cell level, and accordingly the entire cell population expressing the protease can be accurately enumerated. The clear cellular change in fluorescence pattern makes this system an ideal tool for various life science and drug discovery research, including high throughput and high content screening applications.

  13. Development of droplets‐based microfluidic systems for single­‐cell high‐throughput screening

    DEFF Research Database (Denmark)

    Chen, Jun; Jensen, Thomas Glasdam; Godina, Alexei;

    2014-01-01

    investment, and a logarithmic increase to screen large combinatorial libraries over the decades also makes it gradually out of depth. Here, we are trying to develop a feasible high‐throughput system that uses microfluidics to compartmentalize a single cell for propagation and analysis in monodisperse...... picoliter aqueous droplets surround by an immiscible fluorinated oil phase. Our aim is to use this system to facilitate the screening process for both the biotechnology and food industry....

  14. POST-OPERATIVE STAGING AND SURVIVAL BASED ON THE REVISED TNM STAGING SYSTEM FOR NON-SMALL CELL LUNG CANCER

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To study the factors affecting post-operative staging and survival in non-small cell lung cancer (NSCLC) patients based on the revised TNM staging system adopted by the UICC in 1977. Methods: Data were collected from 1757 consecutively operated NSCLC patients, including those receiving complete tumor excision, tumor debulking and exploratory thoractomy from April 1969 through Dec. 1993. the end point of follow-up was Nov. 30, 1998. Cumulative survival and its influencing factors were analyzed by Kaplan-Meier and Cox model of SPSS software. Results: In this series, 30 patients (1.7%) were lost from follow-up. The 5-year cumulative survival was 88.0% for patients in stage I A, and 53.9% in stage IB, 33.5% in stage II, 14.7% in stage IIIA, 5.5% in stage IIIB and 7.0% in stage IV. The overall 5-year survival rate was 28.2%. The 5-year survivals were 39.8%, 14.4% and 4.2% in patients treated with completely tumor resection, tumor debulking and explorative thoractomy, respectively. The 10-year survival rate was 31.4%, 9.5% and 0, respectively. Factors affecting long-term cumulative survival, in the order of decreasing significance, were the type of operation, lymph node status, staging, size and pathological type of the primary tumor. Conclusion: the revised staging system for NSCLC is superior to that used since 1986 as far as the end results of treatment in patients in different stage and the staging specificity are concerned. The T3N1M0 classification and the definition of M1 need to be further studied.

  15. AlgiMatrix™ based 3D cell culture system as an in-vitro tumor model for anticancer studies.

    Directory of Open Access Journals (Sweden)

    Chandraiah Godugu

    Full Text Available BACKGROUND: Three-dimensional (3D in-vitro cultures are recognized for recapitulating the physiological microenvironment and exhibiting high concordance with in-vivo conditions. Taking the advantages of 3D culture, we have developed the in-vitro tumor model for anticancer drug screening. METHODS: Cancer cells grown in 6 and 96 well AlgiMatrix™ scaffolds resulted in the formation of multicellular spheroids in the size range of 100-300 µm. Spheroids were grown in two weeks in cultures without compromising the growth characteristics. Different marketed anticancer drugs were screened by incubating them for 24 h at 7, 9 and 11 days in 3D cultures and cytotoxicity was measured by AlamarBlue® assay. Effectiveness of anticancer drug treatments were measured based on spheroid number and size distribution. Evaluation of apoptotic and anti-apoptotic markers was done by immunohistochemistry and RT-PCR. The 3D results were compared with the conventional 2D monolayer cultures. Cellular uptake studies for drug (Doxorubicin and nanoparticle (NLC were done using spheroids. RESULTS: IC(50 values for anticancer drugs were significantly higher in AlgiMatrix™ systems compared to 2D culture models. The cleaved caspase-3 expression was significantly decreased (2.09 and 2.47 folds respectively for 5-Fluorouracil and Camptothecin in H460 spheroid cultures compared to 2D culture system. The cytotoxicity, spheroid size distribution, immunohistochemistry, RT-PCR and nanoparticle penetration data suggested that in vitro tumor models show higher resistance to anticancer drugs and supporting the fact that 3D culture is a better model for the cytotoxic evaluation of anticancer drugs in vitro. CONCLUSION: The results from our studies are useful to develop a high throughput in vitro tumor model to study the effect of various anticancer agents and various molecular pathways affected by the anticancer drugs and formulations.

  16. Analysis and Comparison Based on Component Stress Factor of Dual Active Bridge and Isolated Full Bridge Boost Converters for Bidirectional Fuel Cells Systems

    DEFF Research Database (Denmark)

    Pittini, Riccardo; Mira Albert, Maria del Carmen; Zhang, Zhe;

    2014-01-01

    This paper presents an analysis and comparison of isolated topologies for bidirectional fuel cell systems. The analyzed topologies are the dua l active bridge (DAB) and the isolated full bridge boost converter (IFBBC). The analysis is performed based on the component stress factor (CSF). Results ...

  17. Modelling of pressurised hybrid systems based on integrated planar solid oxide fuel cell (IP-SOFC) technology

    Energy Technology Data Exchange (ETDEWEB)

    Magistri, L.; Traverso, A.; Massardo, A.F. [TPG-DIMSET, University of Genoa, Via Montallegro 1, 16145 Genova (Italy); Cerutti, F.; Costamagna, P. [TPG-DICHEP, University of Genoa, Via Opera Pia 15, 16145 Genova (Italy); Bozzolo, M. [Rolls-Royce Fuel Cell Systems Ltd, PO Box 31, Derby DE24 8BJ (United Kingdom)

    2005-02-01

    This work describes different models, developed by the Thermochemical Power Group at the University of Genoa (Italy), for the simulation of solid oxide fuel cell and gas turbine hybrid systems. The paper focuses on both ''cores'' of the system: the fuel cell stack on the one hand and the turbomachinery and the auxiliaries on the other hand. Therefore, in the first part of the paper the models developed for the analysis of the Rolls-Royce Integrated Planar SOFC cells are presented; the results are compared to experimental data, and carefully analysed and discussed. In the second part of the paper, design and off design models of IP-SOFC pressurised hybrid systems in the range 250 kW-20 MW are presented; the hybrid performance results are presented and discussed, also taking ambient condition effects and a possible control strategy into account. Finally, using an in-house general purpose transient system analysis code (TRANSEO code), where chemical composition, heat transfer, and fluid dynamic influences vs. time are considered in detail, a preliminary time dependent investigation of a pressurised hybrid system behaviour is presented. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  18. Universal low-temperature MWCNT-COOH-based counter electrode and a new thiolate/disulfide electrolyte system for dye-sensitized solar cells.

    Science.gov (United States)

    Hilmi, Abdulla; Shoker, Tharallah A; Ghaddar, Tarek H

    2014-06-11

    A new thiolate/disulfide organic-based electrolyte system composed of the tetrabutylammonium salt of 2-methyl-5-trifluoromethyl-2H-[1,2,4]triazole-3-thiol (S(-)) and its oxidized form 3,3'-dithiobis(2-methyl-5-trifluoromethyl-2H-[1,2,4]triazole) (DS) has been formulated and used in dye-sensitized solar cells (DSSCs). The electrocatalytic activity of different counter electrodes (CEs) has been evaluated by means of measuring J-V curves, cyclic voltammetry, Tafel plots, and electrochemical impedance spectroscopy. A stable and low-temperature CE based on acid-functionalized multiwalled carbon nanotubes (MWCNT-COOH) was investigated with our S(-)/DS, I(-)/I3(-), T(-)/T2, and Co(II/III)-based electrolyte systems. The proposed CE showed superb electrocatalytic activity toward the regeneration of the different electrolytes. In addition, good stability of solar cell devices based on the reported electrolyte and CE was shown.

  19. Investigations on an advanced power system based on a high temperature polymer electrolyte membrane fuel cell and an organic Rankine cycle for heating and power production

    International Nuclear Information System (INIS)

    Energy systems based on fuel cells technology can have a strategic role in the range of small-size power generation for the sustainable energy development. In order to enhance their performance, it is possible to recover the “waste heat” from the fuel cells, for producing or thermal power (cogeneration systems) or further electric power by means of a bottoming power cycle (combined systems). In this work an advanced system based on the integration between a HT-PEMFC (high temperature polymer electrolyte membrane fuel cell) power unit and an ORC (organic Rankine cycle) plant, has been proposed and analysed as suitable energy power plant for supplying electric and thermal energies to a stand-alone residential utility. The system can operate both as cogeneration system, in which the electric and thermal loads are satisfied by the HT-PEMFC power unit and as electric generation system, in which the low temperature heat recovered from the fuel cells is used as energy source in the ORC plant for increasing the electric power production. A numerical model, able to characterize the behavior and to predict the performance of the HT-PEMFC/ORC system under different working conditions, has been developed by using the AspenPlus™ code. - Highlights: • The advanced plant can operate both as CHP system and as electric generation system. • The performance prediction of the integrated system is carried out by numerical modeling. • ORC thermodynamic optimization is carried out by a sensitivity analysis. • Thermal coupling between the HT-PEMC system and the ORC plant is analyzed. • Results are very promising in the field of the distributed generation

  20. Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells.

    Science.gov (United States)

    Flaherty, Rebecca A; Lee, Shaun W

    2016-08-19

    Many bacterial pathogens secrete potent toxins to aid in the destruction of host tissue, to initiate signaling changes in host cells or to manipulate immune system responses during the course of infection. Though methods have been developed to successfully purify and produce many of these important virulence factors, there are still many bacterial toxins whose unique structure or extensive post-translational modifications make them difficult to purify and study in in vitro systems. Furthermore, even when pure toxin can be obtained, there are many challenges associated with studying the specific effects of a toxin under relevant physiological conditions. Most in vitro cell culture models designed to assess the effects of secreted bacterial toxins on host cells involve incubating host cells with a one-time dose of toxin. Such methods poorly approximate what host cells actually experience during an infection, where toxin is continually produced by bacterial cells and allowed to accumulate gradually during the course of infection. This protocol describes the design of a permeable membrane insert-based bacterial infection system to study the effects of Streptolysin S, a potent toxin produced by Group A Streptococcus, on human epithelial keratinocytes. This system more closely mimics the natural physiological environment during an infection than methods where pure toxin or bacterial supernatants are directly applied to host cells. Importantly, this method also eliminates the bias of host responses that are due to direct contact between the bacteria and host cells. This system has been utilized to effectively assess the effects of Streptolysin S (SLS) on host membrane integrity, cellular viability, and cellular signaling responses. This technique can be readily applied to the study of other secreted virulence factors on a variety of mammalian host cell types to investigate the specific role of a secreted bacterial factor during the course of infection.

  1. A glycosaminoglycan based, modular tissue scaffold system for rapid assembly of perfusable, high cell density, engineered tissues.

    Directory of Open Access Journals (Sweden)

    Ramkumar Tiruvannamalai-Annamalai

    Full Text Available The limited ability to vascularize and perfuse thick, cell-laden tissue constructs has hindered efforts to engineer complex tissues and organs, including liver, heart and kidney. The emerging field of modular tissue engineering aims to address this limitation by fabricating constructs from the bottom up, with the objective of recreating native tissue architecture and promoting extensive vascularization. In this paper, we report the elements of a simple yet efficient method for fabricating vascularized tissue constructs by fusing biodegradable microcapsules with tunable interior environments. Parenchymal cells of various types, (i.e. trophoblasts, vascular smooth muscle cells, hepatocytes were suspended in glycosaminoglycan (GAG solutions (4%/1.5% chondroitin sulfate/carboxymethyl cellulose, or 1.5 wt% hyaluronan and encapsulated by forming chitosan-GAG polyelectrolyte complex membranes around droplets of the cell suspension. The interior capsule environment could be further tuned by blending collagen with or suspending microcarriers in the GAG solution These capsule modules were seeded externally with vascular endothelial cells (VEC, and subsequently fused into tissue constructs possessing VEC-lined, inter-capsule channels. The microcapsules supported high density growth achieving clinically significant cell densities. Fusion of the endothelialized, capsules generated three dimensional constructs with an embedded network of interconnected channels that enabled long-term perfusion culture of the construct. A prototype, engineered liver tissue, formed by fusion of hepatocyte-containing capsules exhibited urea synthesis rates and albumin synthesis rates comparable to standard collagen sandwich hepatocyte cultures. The capsule based, modular approach described here has the potential to allow rapid assembly of tissue constructs with clinically significant cell densities, uniform cell distribution, and endothelialized, perfusable channels.

  2. Towards increased selectivity of drug delivery to cancer cells: development of a LDL-based nanodelivery system for hydrophobic photosensitizers

    Science.gov (United States)

    Buzova, Diana; Huntosova, Veronika; Kasak, Peter; Petrovajova, Dana; Joniova, Jaroslava; Dzurova, Lenka; Nadova, Zuzana; Sureau, Franck; Midkovsky, Pavol; Jancura, Daniel

    2012-10-01

    Low-density lipoproteins (LDL), a natural in vivo carrier of cholesterol in the vascular system, play a key role in the delivery of hydrophobic photosensitizers (pts) to tumor cells in photodynamic therapy (PDT) of cancer. To make this delivery system even more efficient, we have constructed a nano-delivery system by coating of LDL surface by polyethylene glycol (PEG) and dextran. Fluorescence spectroscopy and confocal fluorescence imaging were used to characterize redistribution of hypericin (Hyp), a natural potent pts, loaded in LDL/PEG and LDL/dextran complexes to free LDL molecules as well as to monitor cellular uptake of Hyp by U87-MG cells. It was shown than the redistribution process of Hyp between LDL molecules is significantly suppressed by dextran coating of LDL surface. On the other hand, PEG does not significantly influence this process. The modification of LDL molecules by the polymers does not inhibit their recognition by cellular LDL receptors. U-87 MG cellular uptake of Hyp loaded in LDL/PEG and LDL/dextran complexes appears to be similar to that one observed for Hyp transported by unmodified LDL particles. It is proposed that by polymers modified LDL molecules could be used as a basis for construction of a drug transport system for targeted delivery of hydrophobic drugs to cancer cells expressing high level of LDL receptors.

  3. High efficiency chemical energy conversion system based on a methane catalytic decomposition reaction and two fuel cells. Part II. Exergy analysis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qinghua; Tian, Ye; Li, Hongjiao; Jia, Lijun; Xia, Chun; Li, Yongdan [Tianjin Key Laboratory of Catalysis Science and Technology and State Key Laboratory for Chemical Engineering (Tianjin University), School of Chemical Engineering, Tianjin University, Tianjin 300072 (China); Thompson, Levi T. [Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109-2136 (United States)

    2010-10-01

    A methane catalytic decomposition reactor-direct carbon fuel cell-internal reforming solid oxide fuel cell (MCDR-DCFC-IRSOFC) energy system is highly efficient for converting the chemical energy of methane into electrical energy. A gas turbine cycle is also used to output more power from the thermal energy generated in the IRSOFC. In part I of this work, models of the fuel cells and the system are proposed and validated. In this part, exergy conservation analysis is carried out based on the developed electrochemical and thermodynamic models. The ratio of the exergy destruction of each unit is examined. The results show that the electrical exergy efficiency of 68.24% is achieved with the system. The possibility of further recovery of the waste heat is discussed and the combined power-heat exergy efficiency is over 80%. (author)

  4. Development of an all-in-one lentiviral vector system based on the original TetR for the easy generation of Tet-ON cell lines.

    Directory of Open Access Journals (Sweden)

    Karim Benabdellah

    Full Text Available Lentiviral vectors (LVs are considered one of the most promising vehicles to efficiently deliver genetic information for basic research and gene therapy approaches. Combining LVs with drug-inducible expression systems should allow tight control of transgene expression with minimal side effect on relevant target cells. A new doxycycline-regulated system based on the original TetR repressor was developed in 1998 as an alternative to the TetR-VP16 chimeras (tTA and rtTA to avoid secondary effects due to the expression of transactivator domains. However, previously described TetR-based systems required cell cloning and/or antibiotic selection of tetracycline-responsive cells in order to achieve good regulation. In the present manuscript we have constructed a dual Tet-ON system based on two lentiviral vectors, one expressing the TetR through the spleen focus forming virus (SFFV promoter (STetR and a second expressing eGFP through the regulatable CMV-TetO promoter (CTetOE. Using these vectors we have demonstrated that the TetR repressor, contrary to the reverse transactivator (rtTA, can be expressed in excess to bind and modulate a high number of TetO operons. We have also showed that this dual vector system can generate regulatable bulk cell lines (expressing high levels of TetR that are able to modulate transgene expression either by varying doxycycline concentration and/or by varying the amount of CTetOE vector genomes per cell. Based on these results we have developed a new all-in-one lentiviral vector (CEST driving the expression of TetR through the SFFV promoter and the expression of eGFP through the doxycycline-responsive CMV-TetO operon. This vector efficiently produced Tet-ON regulatable immortalized (293T and primary (human mesenchymal stem cells and human primary fibroblasts cells. Bulk doxycycline-responsive cell lines express high levels of the transgene with low amount of doxycycline and are phenotypically indistinct from its parental

  5. A plasmacytoid dendritic cell (CD123+/CD11c-) based assay system to predict contact allergenicity of chemicals

    International Nuclear Information System (INIS)

    A predictive allergenicity test system for assessing the contact allergenicity of chemicals is needed by the cosmetic and pharmaceutical industry to monitor product safety in the marketplace. Development of such non-animal alternative assay systems for skin sensitization and hazard identification has been pursued by policy makers and regulatory agencies. We investigated whether phenotypic and functional changes to a subset of dendritic cells (DC), plasmacytoid DC (pDC), could be used to identify contact allergens. To achieve this goal, normal human DC were generated from CD34+ progenitor cells and cryopreserved. Frozen DC were thawed and the pDC fraction (CD123+/CD11c-) was harvested using FACS sorting. The pDC were cultured, expanded, and exposed to chemical allergens (N = 26) or non-allergens (N = 22). Concentrations of each chemical that resulted in >50% viability was determined using FACS analysis of propidium iodide stained cells using pDC from 2 to 5 donors. Expression of the surface marker, CD86, which has been implicated in dendritic cell maturation, was used as a marker of allergenicity. CD86 expression increased (≥1.5-fold) for 25 of 26 allergens (sensitivity = 96%) but did not increase for 19 of 22 non-allergens (specificity = 86%). In a direct comparison to historical data for the regulatory approved, mouse local lymph node assay (LLNA) for 23 allergens and 22 non-allergens, the pDC method had sensitivity and specificity of 96% and 86%, respectively, while the sensitivity and specificity of the LLNA assay was 83% and 82%, respectively. In conclusion, CD86 expression in pDC appears to be a sensitive and specific indicator to identify contact allergenicity. Such an assay method utilizing normal human cells will be useful for high throughput screening of chemicals for allergenicity.

  6. Hydrogel based occlusion systems

    NARCIS (Netherlands)

    Stam, F.A.; Jackson, N.; Dubruel, P.; Adesanya, K.; Embrechts, A.; Mendes, E.; Neves, H.P.; Herijgers, P.; Verbrugghe, Y.; Shacham, Y.; Engel, L.; Krylov, V.

    2013-01-01

    A hydrogel based occlusion system, a method for occluding vessels, appendages or aneurysms, and a method for hydrogel synthesis are disclosed. The hydrogel based occlusion system includes a hydrogel having a shrunken and a swollen state and a delivery tool configured to deliver the hydrogel to a tar

  7. An insert-based enzymatic cell culture system to rapidly and reversibly induce hypoxia: investigations of hypoxia-induced cell damage, protein expression and phosphorylation in neuronal IMR-32 cells

    Directory of Open Access Journals (Sweden)

    Ying Huang

    2013-11-01

    Ischemia-reperfusion injury and tissue hypoxia are of high clinical relevance because they are associated with various pathophysiological conditions such as myocardial infarction and stroke. Nevertheless, the underlying mechanisms causing cell damage are still not fully understood, which is at least partially due to the lack of cell culture systems for the induction of rapid and transient hypoxic conditions. The aim of the study was to establish a model that is suitable for the investigation of cellular and molecular effects associated with transient and long-term hypoxia and to gain insights into hypoxia-mediated mechanisms employing a neuronal culture system. A semipermeable membrane insert system in combination with the hypoxia-inducing enzymes glucose oxidase and catalase was employed to rapidly and reversibly generate hypoxic conditions in the culture medium. Hydrogen peroxide assays, glucose measurements and western blotting were performed to validate the system and to evaluate the effects of the generated hypoxia on neuronal IMR-32 cells. Using the insert-based two-enzyme model, hypoxic conditions were rapidly induced in the culture medium. Glucose concentrations gradually decreased, whereas levels of hydrogen peroxide were not altered. Moreover, a rapid and reversible (onoff generation of hypoxia could be performed by the addition and subsequent removal of the enzyme-containing inserts. Employing neuronal IMR-32 cells, we showed that 3 hours of hypoxia led to morphological signs of cellular damage and significantly increased levels of lactate dehydrogenase (a biochemical marker of cell damage. Hypoxic conditions also increased the amounts of cellular procaspase-3 and catalase as well as phosphorylation of the pro-survival kinase Akt, but not Erk1/2 or STAT5. In summary, we present a novel framework for investigating hypoxia-mediated mechanisms at the cellular level. We claim that the model, the first of its kind, enables researchers to rapidly and

  8. Interference Alignment-based Precoding and User Selection with Limited Feedback in Two-cell Downlink Multi-user MIMO Systems

    Directory of Open Access Journals (Sweden)

    Yin Zhu

    2016-05-01

    Full Text Available Interference alignment (IA is a new approach to address interference in modern multiple-input multiple-out (MIMO cellular networks in which interference is an important factor that limits the system throughput. System throughput in most IA implementation schemes is significantly improved only with perfect channel state information and in a high signal-to-noise ratio (SNR region. Designing a simple IA scheme for the system with limited feedback and investigating system performance at a low-to-medium SNR region is important and practical. This paper proposed a precoding and user selection scheme based on partial interference alignment in two-cell downlink multi-user MIMO systems under limited feedback. This scheme aligned inter-cell interference to a predefined direction by designing user’s receive antenna combining vectors. A modified singular value decomposition (SVD-based beamforming method and a corresponding user-selection algorithm were proposed for the system with low rate limited feedback to improve sum rate performance. Simulation results show that the proposed scheme achieves a higher sum rate than traditional schemes without IA. The modified SVD-based beamforming scheme is also superior to the traditional zero-forcing beamforming scheme in low-rate limited feedback systems. The proposed partial IA scheme does not need to collaborate between transmitters and joint design between the transmitter and the users. The scheme can be implemented with low feedback overhead in current MIMO cellular networks.

  9. A new extranodal scoring system based on the prognostically relevant extranodal sites in diffuse large B-cell lymphoma, not otherwise specified treated with chemoimmunotherapy.

    Science.gov (United States)

    Hwang, Hee Sang; Yoon, Dok Hyun; Suh, Cheolwon; Huh, Jooryung

    2016-08-01

    Extranodal involvement is a well-known prognostic factor in patients with diffuse large B-cell lymphomas (DLBCL). Nevertheless, the prognostic impact of the extranodal scoring system included in the conventional international prognostic index (IPI) has been questioned in an era where rituximab treatment has become widespread. We investigated the prognostic impacts of individual sites of extranodal involvement in 761 patients with DLBCL who received rituximab-based chemoimmunotherapy. Subsequently, we established a new extranodal scoring system based on extranodal sites, showing significant prognostic correlation, and compared this system with conventional scoring systems, such as the IPI and the National Comprehensive Cancer Network-IPI (NCCN-IPI). An internal validation procedure, using bootstrapped samples, was also performed for both univariate and multivariate models. Using multivariate analysis with a backward variable selection, we found nine extranodal sites (the liver, lung, spleen, central nervous system, bone marrow, kidney, skin, adrenal glands, and peritoneum) that remained significant for use in the final model. Our newly established extranodal scoring system, based on these sites, was better correlated with patient survival than standard scoring systems, such as the IPI and the NCCN-IPI. Internal validation by bootstrapping demonstrated an improvement in model performance of our modified extranodal scoring system. Our new extranodal scoring system, based on the prognostically relevant sites, may improve the performance of conventional prognostic models of DLBCL in the rituximab era and warrants further external validation using large study populations. PMID:27167532

  10. A nano-reference-system based on two orthogonal (molecular micro-goniometers: the centrosome of animal cells.

    Directory of Open Access Journals (Sweden)

    Regolini Marco

    2014-12-01

    Full Text Available The centrosome, because of 9-fold-symmetry of its orthogonalcentrioles and their circumferential polarity (nonequivalence of the nine centriolarblades,each one molecularly distinguishable, constitutes a biological discrete interface, composed of two orthogonal macromolecular protractors, capable of recognizing and decoding morphogenetic instructions, translating them and delivering targeted molecular complexes into their expected 3D real location in the cell: like an interface or a wiring device, the centrosome recognizes each targeting sequence, matches it with the corresponding receptor, soconnectingit with the correctly-oriented microtubule, directed and targeted towards the desired definite cortical compartment.Morphogenetic geometric instructions (DNA coded are translated by the centrosome into actual locations in cells, and, as a consequence, macromolecules, labeled by DNA geometric signals, can be correctly delivered into their programmed cell locations. In addition, the centrosome (the most chiral and enantiomorphous cell structure plays a geometric key role in left-right patterning: axial centriole circumferential polarity, if reversely oriented, constitutes a likely molecular base for bilateral symmetry.

  11. A Low-Cost Computer-Controlled Arduino-Based Educational Laboratory System for Teaching the Fundamentals of Photovoltaic Cells

    Science.gov (United States)

    Zachariadou, K.; Yiasemides, K.; Trougkakos, N.

    2012-01-01

    We present a low-cost, fully computer-controlled, Arduino-based, educational laboratory (SolarInsight) to be used in undergraduate university courses concerned with electrical engineering and physics. The major goal of the system is to provide students with the necessary instrumentation, software tools and methodology in order to learn fundamental…

  12. Hydrogen storage properties of TiMn 1.5V 0.2-based alloys for application to fuel cell system

    Science.gov (United States)

    Fang, Fang; Li, Yongtao; Zhang, Qingan; Sun, Liangliang; Shao, Zongping; Sun, Dalin

    To meet the requirements of fuel cell power system for electric bike, the influence of partial substitution of Zr and Cr on hydrogen storage performance of TiMn 1.5V 0.2-based alloys is investigated first, and a hydrogen storage tank is then built using the developed TiMn 1.5V 0.2-based alloy as metal hydride bed and its hydrogen supply ability is further evaluated. It is found that for TiMn 1.5V 0.2-based alloys, the Zr substitution for Ti effectively reduces the plateau pressure but increases the plateau slope, while the partial substitution of Mn by Cr decreases the absorption plateau pressure, leading to a smaller hysteresis factor. After the optimization of components, 6 kg of Ti 0.95Zr 0.05Mn 1.4Cr 0.1V 0.2 alloy powder with 5 wt.% aluminum foam is mixed uniformly to form a metal hydride bed inside the tank. The measurements show that the tank releases up to 82 g of hydrogen to produce a 200 W fuel cell output for 300 min and has a stable cyclic capacity, indicating that hydrogen storage system of TiMn 1.5V 0.2-based alloys for fuel cell power system of electric bike is applicable.

  13. Cell phone based balance trainer

    Directory of Open Access Journals (Sweden)

    Lee Beom-Chan

    2012-02-01

    Full Text Available Abstract Background In their current laboratory-based form, existing vibrotactile sensory augmentation technologies that provide cues of body motion are impractical for home-based rehabilitation use due to their size, weight, complexity, calibration procedures, cost, and fragility. Methods We have designed and developed a cell phone based vibrotactile feedback system for potential use in balance rehabilitation training in clinical and home environments. It comprises an iPhone with an embedded tri-axial linear accelerometer, custom software to estimate body tilt, a "tactor bud" accessory that plugs into the headphone jack to provide vibrotactile cues of body tilt, and a battery. Five young healthy subjects (24 ± 2.8 yrs, 3 females and 2 males and four subjects with vestibular deficits (42.25 ± 13.5 yrs, 2 females and 2 males participated in a proof-of-concept study to evaluate the effectiveness of the system. Healthy subjects used the system with eyes closed during Romberg, semi-tandem Romberg, and tandem Romberg stances. Subjects with vestibular deficits used the system with both eyes-open and eyes-closed conditions during semi-tandem Romberg stance. Vibrotactile feedback was provided when the subject exceeded either an anterior-posterior (A/P or a medial-lateral (M/L body tilt threshold. Subjects were instructed to move away from the vibration. Results The system was capable of providing real-time vibrotactile cues that informed corrective postural responses. When feedback was available, both healthy subjects and those with vestibular deficits significantly reduced their A/P or M/L RMS sway (depending on the direction of feedback, had significantly smaller elliptical area fits to their sway trajectory, spent a significantly greater mean percentage time within the no feedback zone, and showed a significantly greater A/P or M/L mean power frequency. Conclusion The results suggest that the real-time feedback provided by this system can be used

  14. Perfusion based cell culture chips

    DEFF Research Database (Denmark)

    Heiskanen, Arto; Emnéus, Jenny; Dufva, Martin

    2010-01-01

    Performing cell culture in miniaturized perfusion chambers gives possibilities to experiment with cells under near in vivo like conditions. In contrast to traditional batch cultures, miniaturized perfusion systems provide precise control of medium composition, long term unattended cultures...... and tissue like structuring of the cultures. However, as this chapter illustrates, many issues remain to be identified regarding perfusion cell culture such as design, material choice and how to use these systems before they will be widespread amongst biomedical researchers....

  15. A Complete Optical Sensor System Based on a POF-SPR Platform and a Thermo-Stabilized Flow Cell for Biochemical Applications

    Directory of Open Access Journals (Sweden)

    Nunzio Cennamo

    2016-02-01

    Full Text Available An optical sensor platform based on surface plasmon resonance (SPR in a plastic optical fiber (POF integrated into a thermo-stabilized flow cell for biochemical sensing applications is proposed. This device has been realized and experimentally tested by using a classic receptor-analyte assay. For this purpose, the gold surface of the POF was chemically modified through the formation of a self-assembling monolayer. The surface robustness of the POF-SPR platform has been tested for the first time thanks to the flow cell. The experimental results show that the proposed device can be successfully used for label-free biochemical sensing. The final goal of this work is to achieve a complete, small-size, simple to use and low cost optical sensor system. The whole system with the flow cell and the optical sensor are extensively described, together with the experimental results obtained with an immunoglobulin G (IgG/anti-IgG assay.

  16. A Complete Optical Sensor System Based on a POF-SPR Platform and a Thermo-Stabilized Flow Cell for Biochemical Applications.

    Science.gov (United States)

    Cennamo, Nunzio; Chiavaioli, Francesco; Trono, Cosimo; Tombelli, Sara; Giannetti, Ambra; Baldini, Francesco; Zeni, Luigi

    2016-01-01

    An optical sensor platform based on surface plasmon resonance (SPR) in a plastic optical fiber (POF) integrated into a thermo-stabilized flow cell for biochemical sensing applications is proposed. This device has been realized and experimentally tested by using a classic receptor-analyte assay. For this purpose, the gold surface of the POF was chemically modified through the formation of a self-assembling monolayer. The surface robustness of the POF-SPR platform has been tested for the first time thanks to the flow cell. The experimental results show that the proposed device can be successfully used for label-free biochemical sensing. The final goal of this work is to achieve a complete, small-size, simple to use and low cost optical sensor system. The whole system with the flow cell and the optical sensor are extensively described, together with the experimental results obtained with an immunoglobulin G (IgG)/anti-IgG assay. PMID:26861328

  17. A Complete Optical Sensor System Based on a POF-SPR Platform and a Thermo-Stabilized Flow Cell for Biochemical Applications.

    Science.gov (United States)

    Cennamo, Nunzio; Chiavaioli, Francesco; Trono, Cosimo; Tombelli, Sara; Giannetti, Ambra; Baldini, Francesco; Zeni, Luigi

    2016-02-04

    An optical sensor platform based on surface plasmon resonance (SPR) in a plastic optical fiber (POF) integrated into a thermo-stabilized flow cell for biochemical sensing applications is proposed. This device has been realized and experimentally tested by using a classic receptor-analyte assay. For this purpose, the gold surface of the POF was chemically modified through the formation of a self-assembling monolayer. The surface robustness of the POF-SPR platform has been tested for the first time thanks to the flow cell. The experimental results show that the proposed device can be successfully used for label-free biochemical sensing. The final goal of this work is to achieve a complete, small-size, simple to use and low cost optical sensor system. The whole system with the flow cell and the optical sensor are extensively described, together with the experimental results obtained with an immunoglobulin G (IgG)/anti-IgG assay.

  18. Evaluation of a BGO-Based PET System for Single-Cell Tracking Performance by Simulation and Phantom Studies.

    Science.gov (United States)

    Ouyang, Yu; Kim, Tae Jin; Pratx, Guillem

    2016-01-01

    A recent method based on positron emission was reported for tracking moving point sources using the Inveon PET system. However, the effect of scanner background noise was not further explored. Here, we evaluate tracking with the Genisys4, a bismuth germanate-based PET system, which has no significant intrinsic background and may be better suited to tracking lower and/or faster activity sources. Position-dependent sensitivity of the Genisys4 was simulated in Geant4 Application for Tomographic Emission (GATE) using a static (18)F point source. Trajectories of helically moving point sources with varying activity and rotation speed were reconstructed from list-mode data as described previously. Simulations showed that the Inveon's ability to track sources within 2 mm of localization error is limited to objects with a velocity-to-activity ratio like objects with this system. PMID:27175009

  19. An Ag based brazing system with a tunable thermal expansion for the use as sealant for solid oxide cells

    Science.gov (United States)

    Kiebach, Ragnar; Engelbrecht, Kurt; Grahl-Madsen, Laila; Sieborg, Bertil; Chen, Ming; Hjelm, Johan; Norrman, Kion; Chatzichristodoulou, Christodoulos; Hendriksen, Peter Vang

    2016-05-01

    An Ag-Al2TiO5 composite braze was developed and successfully tested as seal for solid oxide cells. The thermo-mechanical properties of the Ag-Al2TiO5 system and the chemical compatibility between this composite braze and relevant materials used in stacks were characterized and the leak rates as a function of the operation temperature were measured. The thermal expansion coefficient in the Ag-Al2TiO5 system can be tailored by varying the amount of the ceramic filler. The brazing process can be carried out in air, the joining partners showed a good chemical stability and sufficient low leak rates were demonstrated. Furthermore, the long-term stability of the Ag-Al2TiO5 composite braze was studied under relevant SOFC and SOEC conditions. The stability of brazed Crofer/Ag-Al2TiO5/NiO-YSZ assemblies in reducing atmosphere and in pure oxygen was investigated over 500 h at 850 °C. Additionally, a cell component test was performed to investigate the durability of the Ag-Al2TiO5 seal when exposed to dual atmosphere. The seals performed well over 900 h under electrolysis operation conditions (-0.5 A cm2, 850 °C), and no cell degradation related to the Ag-Al2TiO5 sealing was found, indicating that the developed braze system is applicable for the use in SOFC/SOEC stacks.

  20. Evaluation of cell lysis procedures and use of a micro fluidic system for an automated DNA-based cell identification in interplanetary missions

    Science.gov (United States)

    Hall, J. A.; Felnagle, E.; Fries, M.; Spearing, S.; Monaco, L.; Steele, A.

    2006-12-01

    A Modular Assay System for Solar System Exploration (MASSE) is being developed to include sample handling, pre-treatment, separation and analysis of biological target compounds by both DNA and protein microarrays. To better design sensitive and accurate initial upstream sample handling of the MASSE instrument, experiments investigating the sensitivity and potential extraction bias of commercially available DNA extraction kits between classes of environmentally relevant prokaryotes such as gram-negative bacteria ( Escherichia coli), gram-positive bacteria ( Bacillus megatarium), and Archaea ( Haloarcula marismortui) were performed. For extractions of both planktonic cultures and spiked Mars simulated regolith, FTA ® paper demonstrated the highest sensitivity, with detection as low as ˜1×10 1 cells and ˜3.3×10 2 cells, respectively. In addition to the highest sensitivity, custom modified application of FTA ® paper extraction protocol is the simplest in terms of incorporation into MASSE and displayed little bias in sensitivity with respect to prokaryotic cell type. The implementation of FTA paper for environmental microbiology investigations appears to be a viable and effective option potentially negating the need for other pre-concentration steps such as filtration and negating concerns regarding extraction efficiency of cells. In addition to investigations on useful technology for upstream sample handling in MASSE, we have also evaluated the potential for μTAS to be employed in the MASSE instrument by employing proprietary lab-on-a-chip development technology to investigate the potential for microfluidic cell lysis of different prokaryotic cells employing both chemical and biological lysis agents. Real-time bright-field microscopy and quantitative PMT detection indicated that that gram positive, gram negative and archaeal cells were effectively lyzed in a few seconds using the microfluidic chip protocol developed. This included employing a lysis buffer with

  1. Systems biomechanics of the cell

    CERN Document Server

    Maly, Ivan V

    2013-01-01

    Systems Biomechanics of the Cell attempts to outline systems biomechanics of the cell as an emergent and promising discipline. The new field owes conceptually to cell mechanics, organism-level systems biomechanics, and biology of biochemical systems. Its distinct methodology is to elucidate the structure and behavior of the cell by analyzing the unintuitive collective effects of elementary physical forces that interact within the heritable cellular framework. The problematics amenable to this approach includes the variety of cellular activities that involve the form and movement of the cell body and boundary (nucleus, centrosome, microtubules, cortex, and membrane). Among the elementary system effects in the biomechanics of the cell, instability of symmetry, emergent irreversibility, and multiperiodic dissipative motion can be noted. Research results from recent journal articles are placed in this unifying framework. It is suggested that the emergent discipline has the potential to expand the spectrum of ques...

  2. Production of oncolytic adenovirus and human mesenchymal stem cells in a single-use, Vertical-Wheel bioreactor system: Impact of bioreactor design on performance of microcarrier-based cell culture processes.

    Science.gov (United States)

    Sousa, Marcos F Q; Silva, Marta M; Giroux, Daniel; Hashimura, Yas; Wesselschmidt, Robin; Lee, Brian; Roldão, António; Carrondo, Manuel J T; Alves, Paula M; Serra, Margarida

    2015-01-01

    Anchorage-dependent cell cultures are used for the production of viruses, viral vectors, and vaccines, as well as for various cell therapies and tissue engineering applications. Most of these applications currently rely on planar technologies for the generation of biological products. However, as new cell therapy product candidates move from clinical trials towards potential commercialization, planar platforms have proven to be inadequate to meet large-scale manufacturing demand. Therefore, a new scalable platform for culturing anchorage-dependent cells at high cell volumetric concentrations is urgently needed. One promising solution is to grow cells on microcarriers suspended in single-use bioreactors. Toward this goal, a novel bioreactor system utilizing an innovative Vertical-Wheel™ technology was evaluated for its potential to support scalable cell culture process development. Two anchorage-dependent human cell types were used: human lung carcinoma cells (A549 cell line) and human bone marrow-derived mesenchymal stem cells (hMSC). Key hydrodynamic parameters such as power input, mixing time, Kolmogorov length scale, and shear stress were estimated. The performance of Vertical-Wheel bioreactors (PBS-VW) was then evaluated for A549 cell growth and oncolytic adenovirus type 5 production as well as for hMSC expansion. Regarding the first cell model, higher cell growth and number of infectious viruses per cell were achieved when compared with stirred tank (ST) bioreactors. For the hMSC model, although higher percentages of proliferative cells could be reached in the PBS-VW compared with ST bioreactors, no significant differences in the cell volumetric concentration and expansion factor were observed. Noteworthy, the hMSC population generated in the PBS-VW showed a significantly lower percentage of apoptotic cells as well as reduced levels of HLA-DR positive cells. Overall, these results showed that process transfer from ST bioreactor to PBS-VW, and scale-up was

  3. Spectrophotometric sensor system based on a liquid waveguide capillary cell for the determination of titanium: Application to natural waters, sunscreens and a lake sediment

    OpenAIRE

    Páscoa, Ricardo N. M. J.; Ildikó V. Tóth; Almeida, Agostinho A.; Rangel, António O. S. S.

    2011-01-01

    An analytical procedure for the spectrophotometric determination of titanium at trace levels was developed. The procedure involves the use of a multipumping flow system (MPFS) coupled with a liquid waveguide capillary cell (LWCC) with 1.0 m path length, 550 mm i.d. and 250 mL internal volume, which enabled to enhance the sensitivity of the determination and thus avoid complex and timeconsuming preconcentration steps. The determination is based on the colorimetric reaction of...

  4. A low-cost computer-controlled Arduino-based educational laboratory system for teaching the fundamentals of photovoltaic cells

    Science.gov (United States)

    Zachariadou, K.; Yiasemides, K.; Trougkakos, N.

    2012-11-01

    We present a low-cost, fully computer-controlled, Arduino-based, educational laboratory (SolarInsight) to be used in undergraduate university courses concerned with electrical engineering and physics. The major goal of the system is to provide students with the necessary instrumentation, software tools and methodology in order to learn fundamental concepts of semiconductor physics by exploring the process of an experimental physics inquiry. The system runs under the Windows operating system and is composed of a data acquisition/control board, a power supply and processing boards, sensing elements, a graphical user interface and data analysis software. The data acquisition/control board is based on the Arduino open source electronics prototyping platform. The graphical user interface and communication with the Arduino are developed in C# and C++ programming languages respectively, by using IDE Microsoft Visual Studio 2010 Professional, which is freely available to students. Finally, the data analysis is performed by using the open source, object-oriented framework ROOT. Currently the system supports five teaching activities, each one corresponding to an independent tab in the user interface. SolarInsight has been partially developed in the context of a diploma thesis conducted within the Technological Educational Institute of Piraeus under the co-supervision of the Physics and Electronic Computer Systems departments’ academic staff.

  5. A low-cost computer-controlled Arduino-based educational laboratory system for teaching the fundamentals of photovoltaic cells

    International Nuclear Information System (INIS)

    We present a low-cost, fully computer-controlled, Arduino-based, educational laboratory (SolarInsight) to be used in undergraduate university courses concerned with electrical engineering and physics. The major goal of the system is to provide students with the necessary instrumentation, software tools and methodology in order to learn fundamental concepts of semiconductor physics by exploring the process of an experimental physics inquiry. The system runs under the Windows operating system and is composed of a data acquisition/control board, a power supply and processing boards, sensing elements, a graphical user interface and data analysis software. The data acquisition/control board is based on the Arduino open source electronics prototyping platform. The graphical user interface and communication with the Arduino are developed in C number sign and C++ programming languages respectively, by using IDE Microsoft Visual Studio 2010 Professional, which is freely available to students. Finally, the data analysis is performed by using the open source, object-oriented framework ROOT. Currently the system supports five teaching activities, each one corresponding to an independent tab in the user interface. SolarInsight has been partially developed in the context of a diploma thesis conducted within the Technological Educational Institute of Piraeus under the co-supervision of the Physics and Electronic Computer Systems departments’ academic staff. (paper)

  6. Hydrogel based occlusion systems

    OpenAIRE

    Stam, F.A.; Jackson, N.; Dubruel, P.; Adesanya, K.; Embrechts, A.; Mendes, E.; Neves, H.P.; Herijgers, P.; Verbrugghe, Y.; Shacham, Y; Engel, L.; Krylov, V.

    2013-01-01

    A hydrogel based occlusion system, a method for occluding vessels, appendages or aneurysms, and a method for hydrogel synthesis are disclosed. The hydrogel based occlusion system includes a hydrogel having a shrunken and a swollen state and a delivery tool configured to deliver the hydrogel to a target occlusion location. The hydrogel is configured to permanently occlude the target occlusion location in the swollen state. The hydrogel may be an electro-activated hydrogel (EAH) which could be ...

  7. Investigation of an integrated hydrogen production system based on nuclear and renewable energy sources: Comparative evaluation of hydrogen production options with a regenerative fuel cell system

    International Nuclear Information System (INIS)

    Hydrogen has risen as a sustainable and efficient energy carrier option in reducing environmental pollution, and is seen as a potential solution for the current energy crisis. Hydrogen production via water decomposition is a potential process for direct utilization of nuclear thermal energy to increase efficiency and thereby facilitate energy savings. While many of the available renewable energy resources are limited due to their reliability, quality, quantity and density, nuclear energy has the potential to contribute a significant share of energy supply with very limited impacts to climate change. The proposed model in this study is an integrated hydrogen production system combining both nuclear and solar energy sources. This integrated system includes storage of hydrogen and its conversion to electricity by a regenerative fuel cell system when needed. There are many matured water splitting processes that can be linked with the nuclear and solar energy sources to decompose water to its constituents, among which is hydrogen. In this regard, a comparative study is carried out to evaluate an optimal and feasible hydrogen production/storage process with a regenerative fuel cell that can be linked to this integrated system. Studies conducted here on hydrogen production processes show the thermochemical water decomposition to be the better option for producing hydrogen, comparing to electrolysis, due to its high efficiencies and low costs. Energy and exergy efficiencies of various hydrogen production processes, and fuel cell systems are evaluated and compared. Also, a parametric study is conducted on these efficiencies to see the effect of various operating conditions. - Highlights: • The proposed model is an integrated hydrogen production system combining both nuclear and solar energies. • Hydrogen production and storage technologies are reviewed comprehensively to determine the most appropriate option. • A comparative analysis is implemented on several hydrogen

  8. Preparation and tumor cell model based biobehavioral evaluation of the nanocarrier system using partially reduced graphene oxide functionalized by surfactant

    Directory of Open Access Journals (Sweden)

    Wang Y

    2015-07-01

    lysosomes in 2 hours through endocytosis, then the drug is released in the cytoplasm in 8 hours, and ultimately EPI is delivered into cell nucleus to exhibit medicinal effects in 1 day.Conclusion: The comprehensive exploration of the biological uptake mechanism of functional graphene-mediated tumor cell targeting model provides a typical protocol for evaluation of drug delivery system and will benefit the discovery of new surfactant-modified nanocarriers in nanomedicine. Keywords: biocompatibility, cytotoxicity, drug delivery, controlled release, fluorescence colocalization, epirubicin

  9. Graphite-based photovoltaic cells

    Science.gov (United States)

    Lagally, Max; Liu, Feng

    2010-12-28

    The present invention uses lithographically patterned graphite stacks as the basic building elements of an efficient and economical photovoltaic cell. The basic design of the graphite-based photovoltaic cells includes a plurality of spatially separated graphite stacks, each comprising a plurality of vertically stacked, semiconducting graphene sheets (carbon nanoribbons) bridging electrically conductive contacts.

  10. In Vitro Testing of Scaffolds for Mesenchymal Stem Cell-Based Meniscus Tissue Engineering—Introducing a New Biocompatibility Scoring System

    Directory of Open Access Journals (Sweden)

    Felix P. Achatz

    2016-04-01

    Full Text Available A combination of mesenchymal stem cells (MSCs and scaffolds seems to be a promising approach for meniscus repair. To facilitate the search for an appropriate scaffold material a reliable and objective in vitro testing system is essential. This paper introduces a new scoring for this purpose and analyzes a hyaluronic acid (HA gelatin composite scaffold and a polyurethane scaffold in combination with MSCs for tissue engineering of meniscus. The pore quality and interconnectivity of pores of a HA gelatin composite scaffold and a polyurethane scaffold were analyzed by surface photography and Berliner-Blau-BSA-solution vacuum filling. Further the two scaffold materials were vacuum-filled with human MSCs and analyzed by histology and immunohistochemistry after 21 days in chondrogenic media to determine cell distribution and cell survival as well as proteoglycan production, collagen type I and II content. The polyurethane scaffold showed better results than the hyaluronic acid gelatin composite scaffold, with signs of central necrosis in the HA gelatin composite scaffolds. The polyurethane scaffold showed good porosity, excellent pore interconnectivity, good cell distribution and cell survival, as well as an extensive content of proteoglycans and collagen type II. The polyurethane scaffold seems to be a promising biomaterial for a mesenchymal stem cell-based tissue engineering approach for meniscal repair. The new score could be applied as a new standard for in vitro scaffold testing.

  11. Establishment and validation of whole-cell based fluorescence assays to identify anti-mycobacterial compounds using the Acanthamoeba castellanii-Mycobacterium marinum host-pathogen system.

    Directory of Open Access Journals (Sweden)

    Sébastien Kicka

    Full Text Available Tuberculosis is considered to be one of the world's deadliest disease with 2 million deaths each year. The need for new antitubercular drugs is further exacerbated by the emergence of drug-resistance strains. Despite multiple recent efforts, the majority of the hits discovered by traditional target-based screening showed low efficiency in vivo. Therefore, there is heightened demand for whole-cell based approaches directly using host-pathogen systems. The phenotypic host-pathogen assay described here is based on the monitoring of GFP-expressing Mycobacterium marinum during infection of the amoeba Acanthamoeba castellanii. The assay showed straight-forward medium-throughput scalability, robustness and ease of manipulation, demonstrating its qualities as an efficient compound screening system. Validation with a series of known antitubercular compounds highlighted the advantages of the assay in comparison to previously published macrophage-Mycobacterium tuberculosis-based screening systems. Combination with secondary growth assays based on either GFP-expressing D. discoideum or M. marinum allowed us to further fine-tune compound characterization by distinguishing and quantifying growth inhibition, cytotoxic properties and antibiotic activities of the compounds. The simple and relatively low cost system described here is most suitable to detect anti-infective compounds, whether they present antibiotic activities or not, in which case they might exert anti-virulence or host defense boosting activities, both of which are largely overlooked by classical screening approaches.

  12. Highly Efficient JFH1-Based Cell-Culture System for Hepatitis C Virus Genotype 5a: Failure of Homologous Neutralizing-Antibody Treatment to Control Infection

    DEFF Research Database (Denmark)

    Jensen, Tanja B; Gottwein, Judith Margarete; Scheel, Troels Kasper Høyer;

    2008-01-01

    Background. @nbsp; Recently, a hepatitis C virus (HCV) cell-culture system was developed that employed strain JFH1 (genotype 2a), and JFH1-based intra- and intergenotypic recombinants now permit functional studies of the structural genes (Core, E1, and E2), p7, and NS2 of genotypes 1-4. The goal...... was to adapt the system to employ genotype 5. Methods. @nbsp; Huh7.5 cells infected with SA13/JFH1, containing Core-NS2 of strain SA13 (genotype 5a), were monitored for Core expression and for supernatant infectivity and HCV-RNA titers. Adaptive mutations of SA13/JFH1 were identified by sequence analysis...

  13. Biosensors and Biofuel Cells based on Vertically Aligned Carbon Nanotubes for Integrated Energy Sensing, Generation, and Storage (SGS) Systems

    Science.gov (United States)

    Pandey, Archana; Prasad, Abhishek; Khin Yap, Yoke

    2010-03-01

    Diabetes is a growing health issue in the nation. Thus in-situ glucose sensors that can monitor the glucose level in our body are in high demand. Furthermore, it will be exciting if the excessive blood sugar can be converted into usable energy, and be stored in miniature batteries for applications. This will be the basis for an integrated energy sensing, generation, and storage (SGS) system in the future. Here we report the use of functionalized carbon nanotubes arrays as the glucose sensors as well as fuel cells that can convert glucose into energy. In principle, these devices can be integrated to detect excessive blood glucose and then convert the glucose into energy. They are also inline with our efforts on miniature 3D microbatteries using CNTs [1]. All these devices will be the basis for future SGS systems. Details of these results will be discussed in the meeting. [1] Wang et al., in 206^th Meeting of the Electrochemical Society, October 3-8, Honolulu, Hawaii (2004), Symposium Q1, abstract 1492. Y. K. Yap acknowledges supports from DARPA (DAAD17-03-C-0115), USDA (2007-35603-17740), and the Multi-Scale Technologies Institute (MuSTI) at MTU.

  14. Electric vehicles and renewable energy in the transport sector - energy system consequences. Main focus: Battery electric vehicles and hydrogen based fuel cell vehicles

    DEFF Research Database (Denmark)

    Nielsen, L.H.; Jørgensen K.

    2000-01-01

    The aim of the project is to analyse energy, environmental and economic aspects of integrating electric vehicles in the future Danish energy system. Consequences of large-scale utilisation of electric vehicles are analysed. The aim is furthermore toillustrate the potential synergistic interplay...... between the utilisation of electric vehicles and large-scale utilisation of fluctuating renewable energy resources, such as wind power. Economic aspects for electric vehicles interacting with a liberalisedelectricity market are analysed. The project focuses on battery electric vehicles and fuel cell...... vehicles based on hydrogen. Based on assumptions on the future technical development for battery electric vehicles, fuel cell vehicles on hydrogen, and forthe conventional internal combustion engine vehicles, scenarios are set up to reflect expected options for the long-term development of road transport...

  15. CFD simulation of Pd-based membrane reformer when thermally coupled within a fuel cell micro-CHP system

    Energy Technology Data Exchange (ETDEWEB)

    Roses, Leonardo; Manzolini, Giampaolo; Campanari, Stefano [Politecnico di Milano, Dipartimento di Energia, Via Lambruschini 4, 20156 Milano (Italy)

    2010-11-15

    In this work, a bi-dimensional CFD simulation investigates a fuel processor for hydrogen production from natural gas or biogas composed by a steam methane reformer coupled with a palladium-based hydrogen permeable membrane, the so-called ''membrane reformer'' (MREF). The heat required for the endothermic reforming reaction taking place on the MREF is supplied by a stream of hot gas coming from an external source, typically represented by a combustor burning the unconverted fuel and the unpermeated hydrogen. The resulting fuel processor arrangement, which has already been simulated by the point of view of energy and mass balances, may achieve a very high efficiency and is particularly suited for integration with fuel cells. The interest on this configuration relies on the possibility to implement this technology within a PEMFC-based micro-cogenerator (also micro-Combined Heat and Power, or m-CHP) with a net electrical power output in a range of 1-2 kW. In particular, the work focuses on the temperature profiles along the membrane, which should be kept as close as possible to 600 C to favourite permeation and avoid any damages, and examines the advantages of hot gas on co-current direction vs. counter-current with respect to the reformer flux direction. (author)

  16. A comparison between molten carbonate fuel cells based hybrid systems using air and supercritical carbon dioxide Brayton cycles with state of the art technology

    Science.gov (United States)

    Sánchez, D.; Muñoz de Escalona, J. M.; Chacartegui, R.; Muñoz, A.; Sánchez, T.

    A proposal for high efficiency hybrid systems based on molten carbonate fuel cells is presented in this paper. This proposal is based on adopting a closed cycle bottoming gas turbine using supercritical carbon dioxide as working fluid as opposed to open cycle hot air turbines typically used in this type of power generators. First, both bottoming cycles are compared for the same operating conditions, showing that their performances do not differ as much as initially expected, even if the initial objective of reducing compression work is accomplished satisfactorily. In view of these results, a profound review of research and industrial literature is carried out in order to determine realistic specifications for the principal components of the bottoming systems. From this analysis, it is concluded that an appropriate set of specifications must be developed for each bottoming cycle as the performances of compressor, turbine and recuperator differ significantly from one working fluid to another. Thus, when the operating conditions are updated, the performances of the resulting systems show a remarkable advantage of carbon dioxide based systems over conventional air units. Actually, the proposed hybrid system shows its capability to achieve 60% net efficiency, what represents a 10% increase with respect to the reference system.

  17. High efficiency chemical energy conversion system based on a methane catalytic decomposition reaction and two fuel cells: Part I. Process modeling and validation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qinghua; Tian, Ye; Li, Hongjiao; Jia, Lijun; Xia, Chun; Li, Yongdan [Tianjin Key Laboratory of Catalysis Science and Technology and State Key Laboratory for Chemical Engineering (Tianjin University), School of Chemical Engineering, Tianjin University, Tianjin 300072 (China); Thompson, Levi T. [Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109-2136 (United States)

    2010-10-01

    A highly efficient integrated energy conversion system is built based on a methane catalytic decomposition reactor (MCDR) together with a direct carbon fuel cell (DCFC) and an internal reforming solid oxide fuel cell (IRSOFC). In the MCDR, methane is decomposed to pure carbon and hydrogen. Carbon is used as the fuel of DCFC to generate power and produce pure carbon dioxide. The hydrogen and unconverted methane are used as the fuel in the IRSOFC. A gas turbine cycle is also used to produce more power output from the thermal energy generated in the IRSOFC. The output performance and efficiency of both the DCFC and IRSOFC are investigated and compared by development of exact models of them. It is found that this system has a unique loading flexibility due to the good high-loading property of DCFC and the good low loading property of IRSOFC. The effects of temperature, pressure, current densities, and methane conversion on the performance of the fuel cells and the system are discussed. The CO{sub 2} emission reduction is effective, up to 80%, can be reduced with the proposed system. (author)

  18. Load-cell based characterization system for a "Violin-Mode" shadow-sensor in advanced LIGO suspensions

    Science.gov (United States)

    Lockerbie, N. A.; Tokmakov, K. V.

    2016-07-01

    The background to this work was a prototype shadow sensor, which was designed for retro-fitting to an advanced LIGO (Laser Interferometer Gravitational wave Observatory) test-mass/mirror suspension, in which 40 kg test-mass/mirrors are each suspended by four approximately 600 mm long by 0.4 mm diameter fused-silica suspension fibres. The shadow sensor comprised a LED source of Near InfraRed (NIR) radiation and a rectangular silicon photodiode detector, which, together, were to bracket the fibre under test. The aim was to detect transverse Violin-Mode resonances in the suspension fibres. Part of the testing procedure involved tensioning a silica fibre sample and translating it transversely through the illuminating NIR beam, so as to measure the DC responsivity of the detection system to fibre displacement. However, an equally important part of the procedure, reported here, was to keep the fibre under test stationary within the beam, whilst trying to detect low-level AC Violin-Mode resonances excited on the fibre, in order to confirm the primary function of the sensor. Therefore, a tensioning system, incorporating a load-cell readout, was built into the test fibre's holder. The fibre then was excited by a signal generator, audio power amplifier, and distant loudspeaker, and clear resonances were detected. A theory for the expected fundamental resonant frequency as a function of fibre tension was developed and is reported here, and this theory was found to match closely with the detected resonant frequencies as they varied with tension. Consequently, the resonances seen were identified as being proper Violin-Mode fundamental resonances of the fibre, and the operation of the Violin-Mode detection system was validated.

  19. LTCC based bioreactors for cell cultivation

    Science.gov (United States)

    Bartsch, H.; Welker, T.; Welker, K.; Witte, H.; Müller, J.

    2016-01-01

    LTCC multilayers offer a wide range of structural options and flexibility of connections not available in standard thin film technology. Therefore they are considered as material base for cell culture reactors. The integration of microfluidic handling systems and features for optical and electrical capturing of indicators for cell culture growth offers the platform for an open system concept. The present paper assesses different approaches for the creation of microfluidic channels in LTCC multilayers. Basic functions required for the fluid management in bioreactors include temperature and flow control. Both features can be realized with integrated heaters and temperature sensors in LTCC multilayers. Technological conditions for the integration of such elements into bioreactors are analysed. The temperature regulation for the system makes use of NTC thermistor sensors which serve as real value input for the control of the heater. It allows the adjustment of the fluid temperature with an accuracy of 0.2 K. The tempered fluid flows through the cell culture chamber. Inside of this chamber a thick film electrode array monitors the impedance as an indicator for the growth process of 3-dimensional cell cultures. At the system output a flow sensor is arranged to monitor the continual flow. For this purpose a calorimetric sensor is implemented, and its crucial design parameters are discussed. Thus, the work presented gives an overview on the current status of LTCC based fluid management for cell culture reactors, which provides a promising base for the automation of cell culture processes.

  20. Targeting CD44 by Hyaluronic Acid-Based Nano Drug Delivery Systems May Eradicate Cancer Stem Cells in Human Breast Cancer

    Directory of Open Access Journals (Sweden)

    Rassoul Dinarvand

    2011-01-01

    Full Text Available Despite the significant progress in cancer diagnosis and therapy, still invasion and metastasis of cancer cells, development of drug resistance and cancer recurrence are the main causes of mortality in cancer patients. Recent researches on cancer stem cells (CSCs along with the role of CD44 marker in drug resistance and as the main marker of breast CSCs, highlight the importance of CD44 in cancer targeted therapy. Additionally, co-localization of MDR1 and CD44 in cancer cell population showed that one protein directly influences the expression of the other and disruption of interaction has significant effects on drug resistance, cell migration and in vitro invasion. Based on the above information, using nanotechnology-derived CD44 targeted drug delivery systems will be able to address recurrence of the disease and other major obstacles in cancer chemotherapy. Therefore, we hypotheses that using combination of cytotoxic agents and CSC specific agents anchored in hyaluronic acid (as the endogenous substrate of CD44, have the potential to develop novel drug delivery systems to eradicate breast cancer.

  1. Fuel cell system with interconnect

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhien; Goettler, Richard; Delaforce, Philip Mark

    2016-03-08

    The present invention includes a fuel cell system having an interconnect that reduces or eliminates diffusion (leakage) of fuel and oxidant by providing an increased densification, by forming the interconnect as a ceramic/metal composite.

  2. Direct methanol feed fuel cell and system

    Science.gov (United States)

    Surampudi, Subbarao (Inventor); Frank, Harvey A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Jeffries-Nakamura, Barbara (Inventor); Kindler, Andrew (Inventor); Halpert, Gerald (Inventor)

    2009-01-01

    Improvements to non acid methanol fuel cells include new formulations for materials. The platinum and ruthenium are more exactly mixed together. Different materials are substituted for these materials. The backing material for the fuel cell electrode is specially treated to improve its characteristics. A special sputtered electrode is formed which is extremely porous. The fuel cell system also comprises a fuel supplying part including a meter which meters an amount of fuel which is used by the fuel cell, and controls the supply of fuel based on said metering.

  3. Characterization of a Solid Oxide Fuel Cell Gas Turbine Hybrid System Based on a Factorial Design of Experiments Using Hardware Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Restrepo, Bernardo; Banta, Larry E; Tucker, David

    2012-10-01

    A full factorial experimental design and a replicated fractional factorial design were carried out using the Hybrid Performance (HyPer) project facility installed at the National Energy Technology Laboratory (NETL), U.S. Department of Energy to simulate gasifer/fuel cell/turbine hybrid power systems. The HyPer facility uses hardware in the loop (HIL) technology that couples a modified recuperated gas turbine cycle with hardware driven by a solid oxide fuel cell model. A 34 full factorial design (FFD) was selected to study the effects of four factors: cold-air, hot-air, bleed-air bypass valves, and the electric load on different parameters such as cathode and turbine inlet temperatures, pressure and mass flow. The results obtained, compared with former results where the experiments were made using one-factor-at-a-time (OFAT), show that no strong interactions between the factors are present in the different parameters of the system. This work also presents a fractional factorial design (ffd) 34-2 in order to analyze replication of the experiments. In addition, a new envelope is described based on the results of the design of experiments (DoE), compared with OFAT experiments, and analyzed in an off-design integrated fuel cell/gas turbine framework. This paper describes the methodology, strategy, and results of these experiments that bring new knowledge concerning the operating state space for this kind of power generation system.

  4. A mammalian cell-based reverse two-hybrid system for functional analysis of 3C viral protease of human enterovirus 71.

    Science.gov (United States)

    Lee, Jin-Ching; Shih, Shin-Ru; Chang, Ten-Yuan; Tseng, Huan-Yi; Shih, Ya-Feng; Yen, Kuei-Jung; Chen, Wei-Chun; Shie, Jiun-Jie; Fang, Jim-Min; Liang, Po-Huang; Chao, Yu-Sheng; Hsu, John T-A

    2008-04-01

    Although several cell-based reporter assays have been developed for screening of viral protease inhibitors, most of these assays have a significant limitation in that numerous false positives can be generated for the compounds that are interfering with reporter gene detection due to the cellular viability. To improve, we developed a mammalian cell-based assay based on the reverse two-hybrid system to monitor the proteolytic activity of human enterovirus 71 (EV71) 3C protease and to validate the cytotoxicity of compounds at the same time. In this system, the GAL4 DNA binding domain (M3) and transactivation domain (VP16) were fused, in-frame, with 3C or 3C(mut). The 3C(mut) was an inactivated protease with mutations at the predicted catalytic triad. The reporter plasmid contains a secreted alkaline phosphatase (SEAP) gene under the control of GAL4 activating sequences. We demonstrated that M3-3C-VP16 failed to turn on the expression of SEAP due to the separation of M3 and the VP16 domains by self-cleavage of 3C. In contrast, SEAP expression was induced by the M3-3C(mut)-VP16 fusion protein or the M3-3C-VP16 in cells treated with AG7088, a potent inhibitor of human rhinoviruses (HRVs) 3C protease. Potentially, this protease detection system should greatly facilitate anti-EV71 drug discovery through a high-throughput screening. PMID:18190777

  5. Optical cell monitoring system for underwater targets

    Science.gov (United States)

    Moon, SangJun; Manzur, Fahim; Manzur, Tariq; Demirci, Utkan

    2008-10-01

    We demonstrate a cell based detection system that could be used for monitoring an underwater target volume and environment using a microfluidic chip and charge-coupled-device (CCD). This technique allows us to capture specific cells and enumerate these cells on a large area on a microchip. The microfluidic chip and a lens-less imaging platform were then merged to monitor cell populations and morphologies as a system that may find use in distributed sensor networks. The chip, featuring surface chemistry and automatic cell imaging, was fabricated from a cover glass slide, double sided adhesive film and a transparent Polymethlymetacrylate (PMMA) slab. The optically clear chip allows detecting cells with a CCD sensor. These chips were fabricated with a laser cutter without the use of photolithography. We utilized CD4+ cells that are captured on the floor of a microfluidic chip due to the ability to address specific target cells using antibody-antigen binding. Captured CD4+ cells were imaged with a fluorescence microscope to verify the chip specificity and efficiency. We achieved 70.2 +/- 6.5% capturing efficiency and 88.8 +/- 5.4% specificity for CD4+ T lymphocytes (n = 9 devices). Bright field images of the captured cells in the 24 mm × 4 mm × 50 μm microfluidic chip were obtained with the CCD sensor in one second. We achieved an inexpensive system that rapidly captures cells and images them using a lens-less CCD system. This microfluidic device can be modified for use in single cell detection utilizing a cheap light-emitting diode (LED) chip instead of a wide range CCD system.

  6. Multifuel burners based on the porous burner technology for the application in fuel cell systems; Mehrstofffaehige Brenner auf Basis der Porenbrennertechnik fuer den Einsatz in Brennstoffzellensystemen

    Energy Technology Data Exchange (ETDEWEB)

    Diezinger, S.

    2006-07-01

    The present doctoral thesis describes the development of multifuel burners based on the porous burner technology for the application in hydrocarbon driven fuel cell systems. One objective of such burners is the heating of the fuel cell system to the operating temperature at the cold start. In stationary operation the burner has to postcombust the waste gases from the fuel cell and the gas processing system in order to reduce the pollutant emissions. As the produced heat is required for endothermal processes like the steam reforming the burner has a significant influence on the system's efficiency. The performed investigations are targeting on a gasoline driven PEMFC-System with steam reforming. In such systems the burner has to be capable to combust the system's fuel gasoline at the cold start, a low calorific fuel cell offgas (HU = 6,4 MJ/kg) in stationary operation and a hydrogen rich gas in the case of an emergency shut down. Pre-tests revealed that in state of the art porous burners the flame front of hydrogen/air combustion can only be stabilized at very high excess air ratios. In basic investigations concerning the stabilization of flame fronts in porous media the dominant influence parameters were determined. Based on this findings a new flame trap was developed which increases the operational range with hydrogen rich mixtures significantly. Furthermore the burning velocity at stationary combustion in porous media was investigated. The dependency of the porous burning velocity on the excess air ratio for different hydrocarbons and hydrogen as well as for mixtures of both was determined. The results of these basic investigations were applied for the design of a multifuel burner. In order to achieve an evaporation of the gasoline without the use of additional energy, an internal heat exchanger section for heating the combustion air was integrated into the burner. Additionally different experimental and numerical methods were applied for designing the

  7. Unitized regenerative fuel cell system

    Science.gov (United States)

    Burke, Kenneth A. (Inventor)

    2008-01-01

    A Unitized Regenerative Fuel Cell system uses heat pipes to convey waste heat from the fuel cell stack to the reactant storage tanks. The storage tanks act as heat sinks/sources and as passive radiators of the waste heat from the fuel cell stack. During charge up, i.e., the electrolytic process, gases are conveyed to the reactant storage tanks by way of tubes that include dryers. Reactant gases moving through the dryers give up energy to the cold tanks, causing water vapor in with the gases to condense and freeze on the internal surfaces of the dryer. During operation in its fuel cell mode, the heat pipes convey waste heat from the fuel cell stack to the respective reactant storage tanks, thereby heating them such that the reactant gases, as they pass though the respective dryers on their way to the fuel cell stacks retrieve the water previously removed.

  8. Designing and optimization of a micro CHP system based on Solid Oxide Fuel Cell with different fuel processing technologies

    DEFF Research Database (Denmark)

    Liso, Vincenzo; Nielsen, Mads Pagh; Kær, Søren Knudsen

    2009-01-01

    The development of fuel cell technologies offers the opportunity to achieve significant improvements in energy conversion efficiencies at many scales. The high operating temperature (700-1000 Celsius) of Solid Oxide Fuel Cells (SOFC) has a number of consequences, the most important of which...

  9. Fuel cell power system for utility vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Graham, M.; Barbir, F.; Marken, F.; Nadal, M. [Energy Partners, Inc., West Palm Beach, FL (United States)

    1996-12-31

    Based on the experience of designing and building the Green Car, a fuel cell/battery hybrid vehicle, and Genesis, a hydrogen/oxygen fuel cell powered transporter, Energy Partners has developed a fuel cell power system for propulsion of an off-road utility vehicle. A 10 kW hydrogen/air fuel cell stack has been developed as a prototype for future mass production. The main features of this stack are discussed in this paper. Design considerations and selection criteria for the main components of the vehicular fuel cell system, such as traction motor, air compressor and compressor motor, hydrogen storage and delivery, water and heat management, power conditioning, and control and monitoring subsystem are discussed in detail.

  10. A cell nanoinjector based on carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xing; Kis, Andras; Zettl, Alex; Bertozzi, Carolyn R.

    2007-01-30

    Technologies for introducing molecules into living cells are vital for probing the physical properties and biochemical interactions that govern the cell's behavior. Here we report the development of a nanoscale cell injection system-termed the nanoinjector-that uses carbon nanotubes to deliver cargo into cells. A single multi-walled carbon nanotube attached to an atomic force microscope tip was functionalized with cargo via a disulfide-based linker. Penetration of cell membranes with this 'nanoneedle', followed by reductive cleavage of the disulfide bonds within the cell's interior, resulted in the release of cargo inside the cells. The capability of the nanoinjector was demonstrated by injection of protein-coated quantum dots into live human cells. Single-particle tracking was employed to characterize the diffusion dynamics of injected quantum dots in the cytosol. This new technique causes no discernible membrane or cell damage, and can deliver a discrete number of molecules to the cell's interior without the requirement of a carrier solvent.

  11. Performance Analysis and Optimum Operation Planning of Distributed Energy System Based on Micro Gas Turbine-Solid Oxide Fuel Cell Hybrid Power Generation

    Science.gov (United States)

    Morita, Aina; Kimijima, Shinji

    In this paper, the economical and energy saving advantages of the distributed energy system, which consists of a micro gas turbine-solid oxide fuel cell hybrid power generation system, waste heat recovery devices and air-conditioning equipments, are investigated. Firstly, the thermodynamical performance evaluation of the hybrid system with the heat recovery devices is discussed to estimate the energy conversion efficiency of the whole system. Secondly, by using 1inear programming technique, the optimum operation planning of the cogeneration plant based on the hybrid system is discussed to predict the reduction of the primary fuel consumption and utility cost. Throughout detailed investigation, it is found that the energy conversion efficiency, which includes the waste heat utilization, reaches over 80% (LHV). In addition, the optimum operation of the hybrid system, of which power generation capacity is appropriate for the energy demand, achieve the highly effective energy saving against the traditional energy supply scheme, that is, the fuel reduction reaches around 40% to the conventional value.

  12. Calculating the Energy Cost of CO2 Removal in a Coal Based Gas Turbine Fuel Cell Hybrid Power Generation System with an Isolated Anode Stream

    Energy Technology Data Exchange (ETDEWEB)

    Vanosdol, J G; Gemmen, R S; Liese, E A

    2007-10-01

    In recent years there has been significant interest in identifying carbon capturing technologies that can be applied to fossil fuel power generation plants.CO2 capture technologies seek to reduce the amount of CO2 that would normally be emitted into the atmosphere from the daily operation of these plants. In terms of system efficiency and operating costs, this carbon capture is expensive. Further, the additional equipment that would be used to capture CO2 emissions greatly adds to the complexity of the system. There has also been significant interest in coal based gas turbine fuel cell hybrid power plants. A hybrid power plant can have much greater system efficiency than a normal gas turbine power plant because the heat that is normally unused in a standalone solid oxide fuel cell (SOFC) is recovered and used to drive a power producing turbine. It is thought that the increased system efficiency of the hybrid system might compensate for the increased expense of performing carbon capture. In order to provide some analytical insight on this tradeoff we present a 100 MW class coal fired gas turbine SOFC hybrid power generation system. The hybrid system operates at a pressure ratio of 6, and uses heat recuperation and cathode air recirculation to control the SOFC inlet temperature and the temperature change across the SOFC. A carbon capture scheme is added to this system in order to calculate the relative energy cost in terms of system efficiency due to CO2 compression. The carbon capture is performed by burning the unused fuel from the SOFC in an isolated anode stream using pure O2 injection. The resulting heat that is generated from this process is then used to drive a secondary turbine that is placed in the anode exhaust stream where more work is extracted. With an isolated anode stream, the products of combustion from this secondary combustion process are mostly water and carbon dioxide. The water by-product is

  13. Machine-vision based optofluidic cell sorting

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Bañas, Andrew

    In contemporary life science there is an increasing emphasis on sorting rare disease-indicating cells within small dilute quantities such as in the confines of optofluidic lab-on-chip devices. Our approach to this is based on the use of optical forces to isolate red blood cells detected by advanced...... machine vision1. This approach is gentler, less invasive and more economical compared to conventional FACS-systems. As cells are less responsive to plastic or glass objects commonly used in the optical manipulation literature2, and since laser safety would be an issue in clinical use, we develop efficient...... the available light and creating 2D or 3D beam distributions aimed at the positions of the detected cells. Furthermore, the beam shaping freedom provided by GPC can allow optimizations in the beam’s propagation and its interaction with the laser catapulted and sorted cells....

  14. Solid polymer MEMS-based fuel cells

    Science.gov (United States)

    Jankowski, Alan F.; Morse, Jeffrey D.

    2008-04-22

    A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. The electrolyte layer can consist of either a solid oxide or solid polymer material, or proton exchange membrane electrolyte materials may be used. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

  15. Solid oxide MEMS-based fuel cells

    Science.gov (United States)

    Jankowksi, Alan F.; Morse, Jeffrey D.

    2007-03-13

    A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. The electrolyte layer can consist of either a solid oxide or solid polymer material, or proton exchange membrane electrolyte materials may be used. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

  16. Design and part-load performance of a hybrid system based on a solid oxide fuel cell reactor and a micro gas turbine

    Science.gov (United States)

    Costamagna, P.; Magistri, L.; Massardo, A. F.

    This paper addresses the design and off-design analysis of a hybrid system (HS) based on the coupling of a recuperated micro gas turbine (MGT) with a high temperature solid oxide fuel cell (SOFC) reactor. The SOFC reactor model is presented and discussed, taking into account the influence of the reactor lay-out, the current density, the air utilisation factor, the cell operating temperature, etc. The SOFC design and off-design performance is presented and discussed; the design and off-design models of a recuperated micro-gas turbine are also presented. The operating line, the influence of the micro gas turbine "variable speed" control, and the efficiency behaviour at part load are analysed in depth. Finally, the model of the hybrid system obtained by coupling the MGT and the SOFC reactor, considering the compatibility (technological constraints) of the two systems, is presented. The model allows the evaluation of the design and off-design behaviour of the hybrid system, particularly when the MGT variable speed control system is considered. The thermal efficiency of the hybrid system, taking into account its size (250/300 kW e), is noteworthy: higher than 60% at design point, and also very high at part load conditions. Such a result is mainly due to the simultaneous positive influence of SOFC off-design behaviour and MGT variable speed control. Moreover, it is possible to recover the waste heat from the gas at the MGT recuperator outlet ( Tgas is about 250°C) for cogeneration purposes.

  17. A Lipid Based Antigen Delivery System Efficiently Facilitates MHC Class-I Antigen Presentation in Dendritic Cells to Stimulate CD8+ T Cells

    Science.gov (United States)

    Maji, Mithun; Mazumder, Saumyabrata; Bhattacharya, Souparno; Choudhury, Somsubhra Thakur; Sabur, Abdus; Shadab, Md.; Bhattacharya, Pradyot; Ali, Nahid

    2016-06-01

    The most effective strategy for protection against intracellular infections such as Leishmania is vaccination with live parasites. Use of recombinant proteins avoids the risks associated with live vaccines. However, due to low immunogenicity, they fail to trigger T cell responses particularly of CD8+ cells requisite for persistent immunity. Previously we showed the importance of protein entrapment in cationic liposomes and MPL as adjuvant for elicitation of CD4+ and CD8+ T cell responses for long-term protection. In this study we investigated the role of cationic liposomes on maturation and antigen presentation capacity of dendritic cells (DCs). We observed that cationic liposomes were taken up very efficiently by DCs and transported to different cellular sites. DCs activated with liposomal rgp63 led to efficient presentation of antigen to specific CD4+ and CD8+ T cells. Furthermore, lymphoid CD8+ T cells from liposomal rgp63 immunized mice demonstrated better proliferative ability when co-cultured ex vivo with stimulated DCs. Addition of MPL to vaccine enhanced the antigen presentation by DCs and induced more efficient antigen specific CD8+ T cell responses when compared to free and liposomal antigen. These liposomal formulations presented to CD8+ T cells through TAP-dependent MHC-I pathway offer new possibilities for a safe subunit vaccine.

  18. Development of a Piggybac based direct reprogramming system for derivation of integration free induced pluripotent stem cells

    OpenAIRE

    Matias, Dino Emanuel Santos

    2013-01-01

    Induced pluripotent stem cells (iPSc) have great potential for applications in regenerative medicine, disease modeling and basic research. Several methods have been developed for their derivation. The original method of Takahashi and Yamanaka involved the use of retroviral vectors which result in insertional mutagenesis, presence in the genome of potential oncogenes and effects of residual transgene expression on differentiation bias of each particular iPSc line. Other methods have been devel...

  19. PROTON EXCHANGE MEMBRANE FUEL CELL SYSTEMS BASED ON AROMATIC HYDROCARBON and PARTIALLY FLUORINATED DISULFONATED POLY(ARYLENE ETHER) COPOLYMERS

    OpenAIRE

    SANKIR, Mehmet

    2005-01-01

    This dissertation describes the past and recent progress in proton exchange membranes (PEM) for fuel cells. In particular the synthesis and characterization of materials for advanced alternative PEM were studied with an emphasis on structure-property and structure-property-performance relationships. The focus has included firstly a one-step synthesis and characterization of 3,3'-disulfonated 4,4'-dichlorodiphenyl sulfone comonomer. The procedure developed is adaptable for industrial-scale ...

  20. Studying Sensing-Based Systems

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    2013-01-01

    Recent sensing-based systems involve a multitude of users, devices, and places. These types of systems challenge existing approaches for conducting valid system evaluations. Here, the author discusses such evaluation challenges and revisits existing system evaluation methodologies....

  1. On-Orbit, Immuno-Based, Label-Free White Blood Cell Counting System with Microelectromechanical Sensor Technology (OILWBCS-MEMS)

    Science.gov (United States)

    Edmonds, Jessica

    2015-01-01

    Aurora Flight Sciences, in partnership with Draper Laboratory, has developed a miniaturized system to count white blood cells in microgravity environments. The system uses MEMS technology to simultaneously count total white blood cells, the five white blood cell differential subgroups, and various lymphocyte subtypes. The OILWBCS-MEMS detection technology works by immobilizing an array of white blood cell-specific antibodies on small, gold-coated membranes. When blood flows across the membranes, specific cells' surface protein antigens bind to their corresponding antibodies. This binding can be measured and correlated to cell counts. In Phase I, the partners demonstrated surface chemistry sensitivity and specificity for total white blood cells and two lymphocyte subtypes. In Phase II, a functional prototype demonstrated end-to-end operation. This rugged, miniaturized device requires minimal blood sample preparation and will be useful for both space flight and terrestrial applications.

  2. Isolation of proflavine as a blocker of G protein-gated inward rectifier potassium channels by a cell growth-based screening system.

    Science.gov (United States)

    Kawada, Hitoshi; Inanobe, Atsushi; Kurachi, Yoshihisa

    2016-10-01

    The overexpression of Kir3.2, a subunit of the G protein-gated inwardly rectifying K(+) channel, is implicated in some of the neurological phenotypes of Down syndrome (DS). Chemical compounds that block Kir3.2 are expected to improve the symptoms of DS. The purpose of this study is to develop a cell-based screening system to identify Kir3.2 blockers and then investigate the mode of action of the blocker. Chemical screening was carried out using a K(+) transporter-deficient yeast strain that expressed a constitutively active Kir3.2 mutant. The mode of action of an effective blocker was electrophysiologically analyzed using Kir channels expressed in Xenopus oocytes. Proflavine was identified to inhibit the growth of Kir3.2-transformant cells and Kir3.2 activity in a concentration-dependent manner. The current inhibition was strong when membrane potentials (Vm) was above equilibrium potential of K(+) (EK). When Vm was below EK, the blockage apparently depended on the difference between Vm and [K(+)]. Furthermore, the inhibition became stronger by lowering extracellular [K(+)]. These results indicated that the yeast strain serves as a screening system to isolate Kir3.2 blockers and proflavine is a prototype of a pore blocker of Kir3.2. PMID:27236080

  3. Electric vehicles and renewable energy in the transport sector - energy system consequences. Main focus: Battery electric vehicles and hydrogen based fuel cell vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, L.H.; Joergensen, K.

    2000-04-01

    The aim of the project is to analyse energy, environmental and economic aspects of integrating electric vehicles in the future Danish energy system. Consequences of large-scale utilisation of electric vehicles are analysed. The aim is furthermore to illustrate the potential synergistic interplay between the utilisation of electric vehicles and large-scale utilisation of fluctuating renewable energy resources, such as wind power. Economic aspects for electric vehicles interacting with a liberalised electricity market are analysed. The project focuses on battery electric vehicles and fuel cell vehicles based on hydrogen. Based on assumptions on the future technical development for battery electric vehicles, fuel cell vehicles on hydrogen, and for the conventional internal combustion engine vehicles, scenarios are set up to reflect expected options for the long-term development of road transport vehicles. Focus is put on the Danish fleet of passenger cars and delivery vans. The scenario analysis includes assumptions on market potential developments and market penetration for the alternative vehicles. Vehicle replacement rates in the Danish transport fleet and the size of fleet development are based on data from The Danish Road Directorate. The electricity supply system development assumed is based on the Danish energy plan, Energy 21, The Plan scenario. The time horizon of the analysis is year 2030. Results from the scenario analysis include the time scales involved for the potential transition towards electricity based vehicles, the fleet composition development, the associated developments in transport fuel consumption and fuel substitution, and the potential CO{sub 2}-emission reduction achievable in the overall transport and power supply system. Detailed model simulations, on an hourly basis, have furthermore been carried out for year 2005 that address potential electricity purchase options for electric vehicles in the context of a liberalised electricity market

  4. Electric vehicles and renewable energy in the transport sector - energy system consequences. Main focus: Battery electric vehicles and hydrogen based fuel cell vehicles

    International Nuclear Information System (INIS)

    The aim of the project is to analyse energy, environmental and economic aspects of integrating electric vehicles in the future Danish energy system. Consequences of large-scale utilisation of electric vehicles are analysed. The aim is furthermore to illustrate the potential synergistic interplay between the utilisation of electric vehicles and large-scale utilisation of fluctuating renewable energy resources, such as wind power. Economic aspects for electric vehicles interacting with a liberalised electricity market are analysed. The project focuses on battery electric vehicles and fuel cell vehicles based on hydrogen. Based on assumptions on the future technical development for battery electric vehicles, fuel cell vehicles on hydrogen, and for the conventional internal combustion engine vehicles, scenarios are set up to reflect expected options for the long-term development of road transport vehicles. Focus is put on the Danish fleet of passenger cars and delivery vans. The scenario analysis includes assumptions on market potential developments and market penetration for the alternative vehicles. Vehicle replacement rates in the Danish transport fleet and the size of fleet development are based on data from The Danish Road Directorate. The electricity supply system development assumed is based on the Danish energy plan, Energy 21, The Plan scenario. The time horizon of the analysis is year 2030. Results from the scenario analysis include the time scales involved for the potential transition towards electricity based vehicles, the fleet composition development, the associated developments in transport fuel consumption and fuel substitution, and the potential CO2-emission reduction achievable in the overall transport and power supply system. Detailed model simulations, on an hourly basis, have furthermore been carried out for year 2005 that address potential electricity purchase options for electric vehicles in the context of a liberalised electricity market. The

  5. Branched DNA-based Alu quantitative assay for cell-free plasma DNA levels in patients with sepsis or systemic inflammatory response syndrome.

    Science.gov (United States)

    Hou, Yan-Qiang; Liang, Dong-Yu; Lou, Xiao-Li; Zhang, Mei; Zhang, Zhen-huan; Zhang, Lu-rong

    2016-02-01

    Cell-free circulating DNA (cf-DNA) can be detected by various of laboratory techniques. We described a branched DNA-based Alu assay for measuring cf-DNA in septic patients. Compared to healthy controls and systemic inflammatory response syndrome (SIRS) patients, serum cf-DNA levels were significantly higher in septic patients (1426.54 ± 863.79 vs 692.02 ± 703.06 and 69.66 ± 24.66 ng/mL). The areas under the receiver operating characteristic curve of cf-DNA for normal vs sepsis and SIRS vs sepsis were 0.955 (0.884-1.025), and 0.856 (0.749-0.929), respectively. There was a positive correlation between cf-DNA and interleukin 6 or procalcitonin or Acute Physiology and Chronic Health Evaluation II. The cf-DNA concentration was higher in intensive care unit nonsurviving patients compared to surviving patients (2183.33 ± 615.26 vs 972.46 ± 648.36 ng/mL; P DNA-based Alu assays are feasible and useful to quantify serum cf-DNA levels. Increased cf-DNA levels in septic patients might complement C-reactive protein and procalcitonin in a multiple marker format. Cell-free circulating DNA might be a new marker in discrimination of sepsis and SIRS.

  6. Coal Integrated Gasification Fuel Cell System Study

    Energy Technology Data Exchange (ETDEWEB)

    Chellappa Balan; Debashis Dey; Sukru-Alper Eker; Max Peter; Pavel Sokolov; Greg Wotzak

    2004-01-31

    This study analyzes the performance and economics of power generation systems based on Solid Oxide Fuel Cell (SOFC) technology and fueled by gasified coal. System concepts that integrate a coal gasifier with a SOFC, a gas turbine, and a steam turbine were developed and analyzed for plant sizes in excess of 200 MW. Two alternative integration configurations were selected with projected system efficiency of over 53% on a HHV basis, or about 10 percentage points higher than that of the state-of-the-art Integrated Gasification Combined Cycle (IGCC) systems. The initial cost of both selected configurations was found to be comparable with the IGCC system costs at approximately $1700/kW. An absorption-based CO2 isolation scheme was developed, and its penalty on the system performance and cost was estimated to be less approximately 2.7% and $370/kW. Technology gaps and required engineering development efforts were identified and evaluated.

  7. Adaptive mutations allow establishment of JFH1-based cell culture systems for hepatitis C virus genotype 4A

    DEFF Research Database (Denmark)

    2013-01-01

    transmembrane domain (.alpha.), in the cytoplasmic part (.beta.) or at the NS2/NS3 cleavage site (y). Following transfection of Huh7.5 cells with RNA transcripts, infectious viruses were produced in the ED43/JFH1-.beta. and -y cultures only. Compared to the 2a control virus, production of infectious viruses...... was significantly delayed. However, in subsequent passages efficient spread of infection and high HCV RNA titers were obtained. Infectivity titers were approximately 10-fold lower than for the 2a control virus. Sequence analysis of recovered 4a/2a recombinants from 3 serial passages and subsequent reverse genetic...

  8. AlgiMatrix™ Based 3D Cell Culture System as an In-Vitro Tumor Model for Anticancer Studies

    OpenAIRE

    Godugu, Chandraiah; Patel, Apurva R.; Desai, Utkarsh; Andey, Terrick; Sams, Alexandria; Singh, Mandip

    2013-01-01

    Background Three-dimensional (3D) in-vitro cultures are recognized for recapitulating the physiological microenvironment and exhibiting high concordance with in-vivo conditions. Taking the advantages of 3D culture, we have developed the in-vitro tumor model for anticancer drug screening. Methods Cancer cells grown in 6 and 96 well AlgiMatrix™ scaffolds resulted in the formation of multicellular spheroids in the size range of 100–300 µm. Spheroids were grown in two weeks in cultures without co...

  9. THE APLLICATION OF CELL-ID BASED LOCATION TECHNOLOGY IN HIGHWAY TRAFFIC INFORMATION SYSTEM%CELL-ID定位技术在高速路况信息系统中的应用

    Institute of Scientific and Technical Information of China (English)

    祝瑞

    2013-01-01

    This paper analyzed the location technologies for current mobile network,and combined with the demand characteristics of highway industry,proposed location technology selection for highway traffic information system.On top of this,the principle of application of CELL-ID technology in the system was introduced in this paper.Running results showed that highway traffic information system of CELL-ID based location technology could play an important role for people in green travel.%本文对当前移动网络的定位技术进行了分析研究,并结合高速公路行业的需求特点,对高速路况信息发布系统的定位技术选择给出了建议.在此基础上,对CELL-ID定位技术在系统中的应用原理进行了介绍.运行结果证明,基于CEIL-ID定位技术的高速路况信息系统可为人们的绿色出行发挥重要的作用.

  10. Development of Dendritic Cell System

    Institute of Scientific and Technical Information of China (English)

    Li Wu; Aleksandar Dakic

    2004-01-01

    The dendritic cell system contains conventional dendritic cells (DCs) and plasmacytoid pre-dendritic cells (pDCs). Both DCs and pDCs are bone marrow derived cells. Although the common functions of DCs are antigen-processing and T-lymphocyte activation, they differ in surface markers, migratory patterns, and cytokine output. These differences can determine the fate of the T cells they activate. Several subsets of mature DCs have been described in both mouse and human and the developmental processes of these specialized DC subsets have been studied extensively. The original concept that all DCs were of myeloid origin was questioned by several recent studies, which demonstrated that in addition to the DCs derived from myeloid precursors,some DCs could also be efficiently generated from lymphoid-restricted precursors. Moreover, it has been shown recently that both conventional DCs and pDCs can be generated by the Flt3 expressing hemopoietic progenitors regardless of their myeloid- or lymphoid-origin. These findings suggest an early developmental flexibility of precursors for DCs and pDCs. This review summarizes some recent observations on the development of DC system in both human and mouse.

  11. Application of an improved operational strategy for a high temperature-proton exchange membrane fuel cell-based micro-combined heat and power system for Danish single-family households

    DEFF Research Database (Denmark)

    Arsalis, Alexandros; Nielsen, Mads Pagh; Kær, Søren Knudsen

    2013-01-01

    characteristics. Based on these findings, an improved operational strategy is formulated and applied in an attempt to minimize the shortcomings of conventional strategies. System parameters, such as electrical and thermal efficiencies, heat dumping, and import/export of electricity, are analyzed. The applied load...... be justified as compared to other micro-CHP system technologies. The most important findings of this research study indicate that in comparison to non-fuel cell-based micro-CHP systems, such as Stirling Engine-based systems, the proposed system has significantly higher efficiencies. Moreover, the lower heat...

  12. Configurable impedance matching to maximise power extraction for enabling self-powered system based-on photovoltaic cells

    Science.gov (United States)

    Rahman, Airul Azha Abd; Jamil, Wan Adil Wan; Umar, Akrajas Ali

    2016-07-01

    Multivariate energy harvesting system, solar and thermal energies, with configurable impedance matching features is presented. The system consists of a tuneable mechanism for peak performance tracking. The inputs are voltages ranging from 20 mV to 3.1 V. The matching load is individually tuned for photovoltaic and thermoelectric power efficiency not less than 80% and 50% of the open circuit voltage respectively. Of experimentation and analysis has been done, the time it takes to fully charge up to 3.4 V is 23 minutes with the rate of charging is 1.8 mV/sec. Empirical data is presented. [Figure not available: see fulltext.

  13. Moon base reactor system

    Science.gov (United States)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  14. An Ag based brazing system with a tunable thermal expansion for the use as sealant for solid oxide cells

    DEFF Research Database (Denmark)

    Kiebach, Wolff-Ragnar; Engelbrecht, Kurt; Grahl-Madsen, Laila;

    2016-01-01

    as a function of the operation temperature were measured. The thermal expansion coefficient in the Ag-Al2TiO5 system can be tailored by varying the amount of the ceramic filler. The brazing process can be carried out in air, the joining partners showed a good chemical stability and sufficient low leak rates...

  15. Linear DNA for rapid prototyping of synthetic biological circuits in an Escherichia coli based TX-TL cell-free system.

    Science.gov (United States)

    Sun, Zachary Z; Yeung, Enoch; Hayes, Clarmyra A; Noireaux, Vincent; Murray, Richard M

    2014-06-20

    Accelerating the pace of synthetic biology experiments requires new approaches for rapid prototyping of circuits from individual DNA regulatory elements. However, current testing standards require days to weeks due to cloning and in vivo transformation. In this work, we first characterized methods to protect linear DNA strands from exonuclease degradation in an Escherichia coli based transcription-translation cell-free system (TX-TL), as well as mechanisms of degradation. This enabled the use of linear DNA PCR products in TX-TL. We then compared expression levels and binding dynamics of different promoters on linear DNA and plasmid DNA. We also demonstrated assembly technology to rapidly build circuits entirely in vitro from separate parts. Using this strategy, we prototyped a four component genetic switch in under 8 h entirely in vitro. Rapid in vitro assembly has future applications for prototyping multiple component circuits if combined with predictive computational models.

  16. Novel organ-slice culturing system to simulate meniscal repair: Proof of concept using a synovium-based pool of meniscoprogenitor cells.

    Science.gov (United States)

    Hunziker, Ernst B; Lippuner, Kurt; Keel, Marius J B; Shintani, Nahoko

    2016-09-01

    Meniscal injuries can occur secondary to trauma or be instigated by the changes in knee-joint function that are associated with aging, osteo- and rheumatoid arthritis, disturbances in gait, and obesity. Sixty percent of persons over 50 years of age manifest signs of meniscal pathology. The surgical and arthroscopic measures that are currently implemented to treat meniscal deficiencies bring only transient relief from pain and effect but a temporary improvement in joint function. Although tissue-engineering-based approaches to meniscal repair are now being pursued, an appropriate in-vitro model has not been conceived. The aim of this study was to develop an organ-slice culturing system to simulate the repair of human meniscal lesions in vitro. The model consists of a ring of bovine meniscus enclosing a chamber that represents the defect and reproduces its sequestered physiological microenvironment. The defect, which is closed with a porous membrane, is filled with fragments of synovial tissue, as a source of meniscoprogenitor cells, and a fibrin-embedded, calcium-phosphate-entrapped depot of the meniscogenic agents BMP-2 and TGF-β1. After culturing for 2 to 6 weeks, the constructs were evaluated histochemically and histomorphometrically, as well as immunohistochemically, for the apoptotic marker caspase 3 and collagen types I and II. Under the defined conditions, the fragments of synovium underwent differentiation into meniscal tissue, which bonded with the parent meniscal wall. Both the parent and the neoformed meniscal tissue survived the duration of the culturing period without significant cell losses. The concept on which the in-vitro system is based was thus validated. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1588-1596, 2016.

  17. Atomic Force Microscopy Based Cell Shape Index

    Science.gov (United States)

    Adia-Nimuwa, Usienemfon; Mujdat Tiryaki, Volkan; Hartz, Steven; Xie, Kan; Ayres, Virginia

    2013-03-01

    Stellation is a measure of cell physiology and pathology for several cell groups including neural, liver and pancreatic cells. In the present work, we compare the results of a conventional two-dimensional shape index study of both atomic force microscopy (AFM) and fluorescent microscopy images with the results obtained using a new three-dimensional AFM-based shape index similar to sphericity index. The stellation of astrocytes is investigated on nanofibrillar scaffolds composed of electrospun polyamide nanofibers that has demonstrated promise for central nervous system (CNS) repair. Recent work by our group has given us the ability to clearly segment the cells from nanofibrillar scaffolds in AFM images. The clear-featured AFM images indicated that the astrocyte processes were longer than previously identified at 24h. It was furthermore shown that cell spreading could vary significantly as a function of environmental parameters, and that AFM images could record these variations. The new three-dimensional AFM-based shape index incorporates the new information: longer stellate processes and cell spreading. The support of NSF PHY-095776 is acknowledged.

  18. Carbon-based Fuel Cell

    Energy Technology Data Exchange (ETDEWEB)

    Steven S. C. Chuang

    2005-08-31

    The direct use of coal in the solid oxide fuel cell to generate electricity is an innovative concept for power generation. The C-fuel cell (carbon-based fuel cell) could offer significant advantages: (1) minimization of NOx emissions due to its operating temperature range of 700-1000 C, (2) high overall efficiency because of the direct conversion of coal to CO{sub 2}, and (3) the production of a nearly pure CO{sub 2} exhaust stream for the direct CO{sub 2} sequestration. The objective of this project is to determine the technical feasibility of using a highly active anode catalyst in a solid oxide fuel for the direct electrochemical oxidation of coal to produce electricity. Results of this study showed that the electric power generation from Ohio No 5 coal (Lower Kittanning) Seam, Mahoning County, is higher than those of coal gas and pure methane on a solid oxide fuel cell assembly with a promoted metal anode catalyst at 950 C. Further study is needed to test the long term activity, selectivity, and stability of anode catalysts.

  19. Energy Systems Based on Polyacetylene: Rechargeable Batteries and Schottky Barrier Solar Cells. Final Report, March 1, 1981-February 29, 1984

    Science.gov (United States)

    MacDiarmid, A. G.

    1984-02-01

    The chief thrust of the research has been directed towards the evaluation of polyacetylene (CH){sub x}, the prototype conducting polymer as an electrode- active material in novel, rechargeable batteries employing nonaqueous electrolytes. The p-doped material, [(CH{sup +y})A{sub y}{sup -}]{sub x}, (where A{sup -} is an anion) in conjunction with a Li anode, shows excellent discharge characteristics, e.g., very little change in discharge voltage with change in discharge current and a high power density. Its energy density is also good but it shows poor shelf life. When (CH){sub x} is used as a cathode (Li anode), which results in the formation of the n-doped polymer, [Li{sub y} {sup +}(CH/sup -y/)]{sub x}, during discharge, good discharge plateaus and power densities are obtained together with excellent shelf life and good recyclability. The energy density is, however only moderate. Cells employing an [M{sub y}{sup +}(CH/sup -y/)]{sub x} (where M = Li, Na) anode and a TiS{sub 2} cathode show very good discharge and recycling characteristics but their energy density is poor.

  20. Disposable self-support paper-based multi-anode microbial fuel cell (PMMFC) integrated with power management system (PMS) as the real time "shock" biosensor for wastewater.

    Science.gov (United States)

    Xu, Zhiheng; Liu, Yucheng; Williams, Isaiah; Li, Yan; Qian, Fengyu; Zhang, Hui; Cai, Dingyi; Wang, Lei; Li, Baikun

    2016-11-15

    A paper-based multi-anode microbial fuel cell (PMMFC) integrated with power management system (PMS) was developed as a disposable self-support real-time "shock" biosensor for wastewater. PMMFCs were examined at three types of shocks (chromium, hypochlorite and acetate) in a batch-mode chamber, and exhibited various responses to shock types and concentrations. The power output of PMMFC sensor was four times as the carbon cloth (CC)-based MFCs, indicating the advantage of paper-based anode for bacterial adhesion. The power output was more sensitive than the voltage output under shocks, and thus preventing the false signals. The simulation of power harvest using PMS indicated that PMMFC could accomplish more frequent data transmission than single-anode MFCs (PSMFC) and CC anode MFCs (CCMMFC), making the self-support wastewater monitor and data transmission possible. Compared with traditional MFC sensors, PMMFCs integrated with PMS exhibit the distinct advantages of tight paper-packed structure, short acclimation period, high power output, and high sensitivity to a wide range of shocks, posing a great potential as "disposable self-support shock sensor" for real time in situ monitoring of wastewater quality. PMID:27179564

  1. Disposable self-support paper-based multi-anode microbial fuel cell (PMMFC) integrated with power management system (PMS) as the real time "shock" biosensor for wastewater.

    Science.gov (United States)

    Xu, Zhiheng; Liu, Yucheng; Williams, Isaiah; Li, Yan; Qian, Fengyu; Zhang, Hui; Cai, Dingyi; Wang, Lei; Li, Baikun

    2016-11-15

    A paper-based multi-anode microbial fuel cell (PMMFC) integrated with power management system (PMS) was developed as a disposable self-support real-time "shock" biosensor for wastewater. PMMFCs were examined at three types of shocks (chromium, hypochlorite and acetate) in a batch-mode chamber, and exhibited various responses to shock types and concentrations. The power output of PMMFC sensor was four times as the carbon cloth (CC)-based MFCs, indicating the advantage of paper-based anode for bacterial adhesion. The power output was more sensitive than the voltage output under shocks, and thus preventing the false signals. The simulation of power harvest using PMS indicated that PMMFC could accomplish more frequent data transmission than single-anode MFCs (PSMFC) and CC anode MFCs (CCMMFC), making the self-support wastewater monitor and data transmission possible. Compared with traditional MFC sensors, PMMFCs integrated with PMS exhibit the distinct advantages of tight paper-packed structure, short acclimation period, high power output, and high sensitivity to a wide range of shocks, posing a great potential as "disposable self-support shock sensor" for real time in situ monitoring of wastewater quality.

  2. Development of Dendritic Cell System

    Institute of Scientific and Technical Information of China (English)

    LiWu; AleksandarDakic

    2004-01-01

    The dendritic cell system contains conventional dendritic cells (DCs) and plasmacytoid pre-dendritic cells (pDCs). Both DCs and pDCs are bone marrow derived calls. Although the common functions of DCs are antigen-processing and T-lymphocyte activation, they differ in surface markers, migratory patterns, and cytokine output. These differences can determine the fate of the T cells they activate. Several subsets of mature DCs have been described in both mouse and human and the developmental processes of these specialized DC subsets have been studied extensively. The original concept that all DCs were of myeloid origin was questioned by several recent studies, which demonstrated that in addition to the DCs derived from myeloid precursors, some DCs could also be efficiently generated from lymphoid-restricted precursors. Moreover, it has been shown recently that both conventional DCs and pDCs can be generated by the Fit3 expressing hemopoietic progenitors regardless of their myeloid- or lymphoid-origin. These findings suggest an early developmental flexibility of precursors for DCs and pDCs. This review summarizes some recent observations on the development of DC system in both human and mouse. Cellular & Molecular Immunology. 2004;1(2):112-118.

  3. Polymer-based solar cells

    Directory of Open Access Journals (Sweden)

    Alex C. Mayer

    2007-11-01

    Full Text Available A significant fraction of the cost of solar panels comes from the photoactive materials and sophisticated, energy-intensive processing technologies. Recently, it has been shown that the inorganic components can be replaced by semiconducting polymers capable of achieving reasonably high power conversion efficiencies. These polymers are inexpensive to synthesize and can be solution-processed in a roll-to-roll fashion with high throughput. Inherently poor polymer properties, such as low exciton diffusion lengths and low mobilities, can be overcome by nanoscale morphology. We discuss polymer-based solar cells, paying particular attention to device design and potential improvements.

  4. Capability-based computer systems

    CERN Document Server

    Levy, Henry M

    2014-01-01

    Capability-Based Computer Systems focuses on computer programs and their capabilities. The text first elaborates capability- and object-based system concepts, including capability-based systems, object-based approach, and summary. The book then describes early descriptor architectures and explains the Burroughs B5000, Rice University Computer, and Basic Language Machine. The text also focuses on early capability architectures. Dennis and Van Horn's Supervisor; CAL-TSS System; MIT PDP-1 Timesharing System; and Chicago Magic Number Machine are discussed. The book then describes Plessey System 25

  5. Evaluation of an AAV2-based rapamycin-regulated glial cell line-derived neurotrophic factor (GDNF expression vector system.

    Directory of Open Access Journals (Sweden)

    Piotr Hadaczek

    Full Text Available Effective regulation of transgene product in anatomically circumscribed brain tissue is dependent on the pharmacokinetics of the regulating agent, the kinetics of transcriptional activation and degradation of the transgene product. We evaluated rapamycin-regulated AAV2-GDNF expression in the rat brain (striatum. Regulated (a dual-component system: AAV2-FBZhGDNF + AAV2-TF1Nc and constitutive (CMV-driven expression vectors were compared. Constitutively active AAV2-GDNF directed stable GDNF expression in a dose-dependent manner and it increased for the first month, thereafter reaching a plateau that was maintained over a further 3 months. For the AAV2-regGDNF, rapamycin was administered in a 3-days on/4-days off cycle. Intraperitoneal, oral, and direct brain delivery (CED of rapamycin were evaluated. Two cycles of rapamycin at an intraperitoneal dose of 10 mg/kg gave the highest GDNF level (2.75±0.01 ng/mg protein. Six cycles at 3 mg/kg resulted in lower GDNF values (1.36±0.3 ng/mg protein. Interestingly, CED of rapamycin into the brain at a very low dose (50 ng induced GDNF levels comparable to a 6-week intraperitoneal rapamycin cycle. This study demonstrates the effectiveness of rapamycin regulation in the CNS. However, the kinetics of the transgene in brain tissue, the regulator dosing amount and schedule are critical parameters that influence the kinetics of accumulation and zenith of the encoded transgene product.

  6. Intelligence-based systems engineering

    CERN Document Server

    Tolk, Andreas

    2011-01-01

    The International Council on Systems Engineering (INCOSE) defines Systems Engineering as an interdisciplinary approach and means to enable the realization of successful systems. Researchers are using intelligence-based techniques to support the practices of systems engineering in an innovative way. This research volume includes a selection of contributions by subject experts to design better systems.

  7. Generation System of Concentrator Photovoltaic Based on Gallium Arsenide Cells%基于砷化镓电池的聚光光伏发电系统

    Institute of Scientific and Technical Information of China (English)

    宁铎; 王辉辉; 黄建兵; 李明勇

    2011-01-01

    Solar photovoltaic power generation system for the problem of low utilization, a generation system of concentrator photovoltaic (CPV) based on gallium arsenide (GaAs) cells can be designed. The system consists of concentrating power modules, solar tracking module, inverter module. Fresnel lens concentrator power generation module 400 times by concentrating light in lcm2 GaAs after the battery,the realization of power function; sun-tracking modules and optical sensors from the head to ensure that the basic vertical sunlight through the Fresnel lens; GaAs inverter module converts DC battery AC issued. After testing, the system reached 20. 2% conversion efficiency of solar, inverter part of the realization of the exchange function of the DC variable.%针对光伏发电系统中太阳能利用率低的问题,设计了一种基于砷化镓(GaAs)电池的聚光光伏(CPV)发电系统;该系统由聚光发电模块、太阳跟踪模块和逆变模块组成;聚光发电模块采用菲涅尔透镜400倍聚光以后照射在1Cmz的砷化镓电池上,实现发电功能;太阳跟踪模块由云台和光电传感器组成,保证太阳光基本垂直通过菲涅尔透镜,逆变模块将砷化镓电池发出的直流电转换成交流电;经过测试.该系统太阳能转换效率达到20.2%,逆变部分实现了直流变交流功能.

  8. Auxiliary pattern for cell-based OPC

    Science.gov (United States)

    Kahng, Andrew B.; Park, Chul-Hong

    2006-10-01

    The runtime of model-based optical proximity correction (OPC) tools has grown unacceptably with each successive technology generation, and has emerged as one of the major bottlenecks for turnaround time (TAT) of IC data preparation and manufacturing. The cell-based OPC approach improves runtime by performing OPC once per cell definition as opposed to once per cell instantiation in the layout. However, cell-based OPC does not comprehend inter-cell optical interactions that affect feature printability in a layout context. In this work, we propose auxiliary pattern-enabled cell-based OPC which can minimize the CD differences between cell-based OPC and model-based OPC. To enable effective insertion of auxiliary pattern (AP) in the design, we also propose a post-placement optimization of a standard cell block with respect to detailed placement. By dynamic programming-based placement perturbation, we achieve 100% AP applicability in designs with placement utilizations of cell-based OPC with AP can match gate edge placement error (EPE) count of model-based OPC within 4%. This is an improvement of 90%, on average, over cell-based OPC without APs. The AP-based OPC approach can reduce OPC runtimes versus model-based OPC by up to 40X in our benchmark designs. We can also achieve reduction of GDSII file size and ORC runtimes due to hierarchy maintenance of cell-based OPC.

  9. Ground Based Systems

    OpenAIRE

    2014-01-01

    The Naval Postgraduate School and the Navy’s Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) in collaboration with ProSensing Inc. has modified an X-Band tactical radar system to add a weather observation mode. The new system was named MWR-05XP (Mobile Weather Radar, 2005 X-Band, Phased Array) and is the first mobile, electronically scanned phased array radar developed for weather sensing applications. Key system parameters of the MWR-05XP rapid scanning radar...

  10. Web based Measurement System for Solar Radiation

    OpenAIRE

    Shachi Awasthi; Dr. P. Mor

    2012-01-01

    We present in this paper, the principles of the measurement system for solar radiation, and our implementation using Web based data logging concept. The photocurrent produced by Silicon PN junction is used as a solar radiation transducer, to make it more viable we have used commercially available solar panels as our transducers. Using a silicon solar cell as sensor, a low cost solar radiometer can be constructed. The photocurrent produced by solar cell is electronically tailored to be measure...

  11. Stem cell-based bone repair

    OpenAIRE

    Fei, Yurong; Xu, Ren-He; Hurley, Marja M.

    2012-01-01

    To accelerate bone repair, one strategy is to deliver the cells that make bone. The current review focuses on stem cell-based bone repair. Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) can self-renew unlimitedly and differentiate into the bone forming cells – osteoblasts. Scientists have been actively investigating culture conditions to stably and efficiently induce differentiation of these stem cells into osteoblasts. However, ESCs have the issues of ethnics, immune ...

  12. GFP-based evaluation system of recombinant expression through the secretory pathway in insect cells and its application to the extracellular domains of class C GPCRs

    OpenAIRE

    Ashikawa, Yuji; Ihara, Makoto; Matsuura, Noriko; Fukunaga, Yuko; Kusakabe, Yuko; Yamashita, Atsuko

    2011-01-01

    Applications of the GFP-fusion technique have greatly facilitated evaluations of the amounts and qualities of sample proteins used for structural analyses. In this study, we applied the GFP-based sample evaluation to secreted protein expression by insect cells. We verified that a GFP variant, GFPuv, retains proper folding and monodispersity within all expression spaces in Sf9 cells, such as the cytosol, organelles, and even the extracellular space after secretion, and thus can serve as a prop...

  13. Risk-based systems configuration monitoring system

    International Nuclear Information System (INIS)

    The paper presents the work done in the frame of the Research Contract No. 6993/RB - ''Risk based systems configuration monitoring system'' part of the coordinated programme ''Development of safety related expert systems''. The aim of this contract was to develop the prototype of an expert system based on PSA technology to be use for controlling the plant systems configuration taking into account the risk. The software prototype implementation was done using Visual Basic language, under Windows environment. The implemented prototype has the following features: store data/knowledge about components and human factor; store data/knowledge about the plant system and systems components, providing facilities to modify/search data/knowledge, based on the general knowledge; generate the logic model of the system; provide minimal cut sets and path sets determination; provide information to be used by the user for configuration risk management; provide user friendly interface (graphical interface under windows). The prototype can be independently used as an operator support system or for other on-line or off-line applications. After the testing of the prototype, some of the conclusions are: the developed software can be one of the most useful tools to be used by designers, PSA analysts, operators and regulatory for evaluation of the safety and reliability of the plant systems; the structure of the General Knowledge Base included into the prototype offers the possibility to combine knowledge introduced by different users. This feature can be the basis for the development of a knowledge acquisition system; the developed software and methodology can offer the basis for the risk-based data collection system development. (author). 12 refs, 30 figs

  14. Cell-Based Therapies for Diabetic Complications

    Directory of Open Access Journals (Sweden)

    Stella Bernardi

    2012-01-01

    Full Text Available In recent years, accumulating experimental evidence supports the notion that diabetic patients may greatly benefit from cell-based therapies, which include the use of adult stem and/or progenitor cells. In particular, mesenchymal stem cells and the circulating pool of endothelial progenitor cells have so far been the most studied populations of cells proposed for the treatment of vascular complications affecting diabetic patients. We review the evidence supporting their use in this setting, the therapeutic benefits that these cells have shown so far as well as the challenges that cell-based therapies in diabetic complications put out.

  15. Heart-on-a-chip based on stem cell biology.

    Science.gov (United States)

    Jastrzebska, Elzbieta; Tomecka, Ewelina; Jesion, Iwona

    2016-01-15

    Heart diseases are one of the main causes of death around the world. The great challenge for scientists is to develop new therapeutic methods for these types of ailments. Stem cells (SCs) therapy could be one of a promising technique used for renewal of cardiac cells and treatment of heart diseases. Conventional in vitro techniques utilized for investigation of heart regeneration do not mimic natural cardiac physiology. Lab-on-a-chip systems may be the solution which could allow the creation of a heart muscle model, enabling the growth of cardiac cells in conditions similar to in vivo conditions. Microsystems can be also used for differentiation of stem cells into heart cells, successfully. It will help better understand of proliferation and regeneration ability of these cells. In this review, we present Heart-on-a-chip systems based on cardiac cell culture and stem cell biology. This review begins with the description of the physiological environment and the functions of the heart. Next, we shortly described conventional techniques of stem cells differentiation into the cardiac cells. This review is mostly focused on describing Lab-on-a-chip systems for cardiac tissue engineering. Therefore, in the next part of this article, the microsystems for both cardiac cell culture and SCs differentiation into cardiac cells are described. The section about SCs differentiation into the heart cells is divided in sections describing biochemical, physical and mechanical stimulations. Finally, we outline present challenges and future research concerning Heart-on-a-chip based on stem cell biology.

  16. Cell-Based Genotoxicity Testing

    Science.gov (United States)

    Reifferscheid, Georg; Buchinger, Sebastian

    Genotoxicity test systems that are based on bacteria display an important role in the detection and assessment of DNA damaging chemicals. They belong to the basic line of test systems due to their easy realization, rapidness, broad applicability, high sensitivity and good reproducibility. Since the development of the Salmonella microsomal mutagenicity assay by Ames and coworkers in the early 1970s, significant development in bacterial genotoxicity assays was achieved and is still a subject matter of research. The basic principle of the mutagenicity assay is a reversion of a growth inhibited bacterial strain, e.g., due to auxotrophy, back to a fast growing phenotype (regain of prototrophy). Deeper knowledge of the ­mutation events allows a mechanistic understanding of the induced DNA-damage by the utilization of base specific tester strains. Collections of such specific tester strains were extended by genetic engineering. Beside the reversion assays, test systems utilizing the bacterial SOS-response were invented. These methods are based on the fusion of various SOS-responsive promoters with a broad variety of reporter genes facilitating numerous methods of signal detection. A very important aspect of genotoxicity testing is the bioactivation of ­xenobiotics to DNA-damaging compounds. Most widely used is the extracellular metabolic activation by making use of rodent liver homogenates. Again, genetic engineering allows the construction of highly sophisticated bacterial tester strains with significantly enhanced sensitivity due to overexpression of enzymes that are involved in the metabolism of xenobiotics. This provides mechanistic insights into the toxification and detoxification pathways of xenobiotics and helps explaining the chemical nature of hazardous substances in unknown mixtures. In summary, beginning with "natural" tester strains the rational design of bacteria led to highly specific and sensitive tools for a rapid, reliable and cost effective

  17. Drug carrier systems based on collagen-alginate composite structures for improving the performance of GDNF-secreting HEK293 cells.

    Science.gov (United States)

    Lee, M; Lo, A C; Cheung, P T; Wong, D; Chan, B P

    2009-02-01

    Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor. Development of drug delivery technologies facilitating controlled release of GDNF is critical to applying GDNF in treating neurodegenerative diseases. We previously developed 3D collagen microspheres and demonstrated enhanced GDNF secretion after encapsulation of HEK293 cells, which were transduced to overexpress GDNF in these microspheres. However, the entrapped HEK293 cells were able to migrate out of the collagen microspheres, making it undesirable for clinical applications. In this report, we investigate two new carrier designs, namely collagen-alginate composite gel and collagen microspheres embedded in alginate gel in preventing cell leakage, maintaining cell growth and controlling GDNF secretion in the HEK293 cells. We demonstrated that inclusion of alginate gel in both designs is efficient in preventing cell leakage to the surrounding yet permitting the GDNF secretion, although the cellular growth rate is reduced in an alginate concentration dependent manner. Differential patterns of GDNF secretion in the two designs were demonstrated. The collagen-alginate composite gel maintains a more or less constant GDNF secretion over time while the collagen microspheres embedded in alginate gel continue to increase the secretion level of GDNF over time. This study contributes towards the development of cell-based GDNF delivery devices for the future therapeutics of neurodegenerative diseases. PMID:19059641

  18. SECA Coal-Based Systems

    Energy Technology Data Exchange (ETDEWEB)

    Pierre, Joseph

    2010-09-10

    This report documents the results of Cooperative Agreement DE-FC26-05NT42613 between Siemens Energy and the U.S. Department of Energy for the period October 1, 2008 through September 30, 2010. The Phase I POCD8R0 stack test was successfully completed as it operated for approximately 5,300 hrs and achieved all test objectives. The stack test article contained twenty-four 75 cm active length Delta8 scandiastabilized zirconia cells. Maximum power was approximately 10 kWe and the SOFC generator demonstrated an availability factor of 85% at 50% power or greater. The Phase II POCD8R1 stack test operated for approximately 410 hrs before being aborted due to a sudden decrease in voltage accompanied by a rapid increase in temperature. The POCD8R1 test article contained forty-eight 100 cm active length Delta8 scandiastabilized zirconia cells arranged in an array of six bundles, with each bundle containing eight cells. Cell development activities resulted in an approximate 100% improvement in cell power at 900°C. Cell manufacturing process improvements led to manufacturing yields of greater than 40% for the Delta8 cells. Delta8 cells with an active length of 100 cm were successfully manufactured as were cells with a seamless closed end. A pressurized cell test article was assembled, installed into the pressurized test facility and limited pressurized testing conducted. Open circuit voltage tests were performed at one and three atmospheres at 950°C were in agreement with the theoretical increase in the Nernst potential. Failed guard heaters precluded further testing. The SOFC analytical basis for the baseline system was validated with experimental data. Two system configurations that utilize a pressurized SOFC design with separated anode and cathode streams were analyzed. System efficiencies greater than 60% were predicted when integrating the separated anode and cathode stream module configuration with a high efficiency catalytic gasifier.

  19. SECA Coal-Based Systems

    Energy Technology Data Exchange (ETDEWEB)

    Joseph Pierre

    2010-09-01

    This report documents the results of Cooperative Agreement DE-FC26-05NT42613 between Siemens Energy and the U.S. Department of Energy for the period October 1, 2008 through September 30, 2010. The Phase I POCD8R0 stack test was successfully completed as it operated for approximately 5,300 hrs and achieved all test objectives. The stack test article contained twenty-four 75 cm active length Delta8 scandia-stabilized zirconia cells. Maximum power was approximately 10 kWe and the SOFC generator demonstrated an availability factor of 85% at 50% power or greater. The Phase II POCD8R1 stack test operated for approximately 410 hrs before being aborted due to a sudden decrease in voltage accompanied by a rapid increase in temperature. The POCD8R1 test article contained forty-eight 100 cm active length Delta8 scandia-stabilized zirconia cells arranged in an array of six bundles, with each bundle containing eight cells. Cell development activities resulted in an approximate 100% improvement in cell power at 900°C. Cell manufacturing process improvements led to manufacturing yields of greater than 40% for the Delta8 cells. Delta8 cells with an active length of 100 cm were successfully manufactured as were cells with a seamless closed end. A pressurized cell test article was assembled, installed into the pressurized test facility and limited pressurized testing conducted. Open circuit voltage tests were performed at one and three atmospheres at 950°C were in agreement wi th the theoretical increase in the Nernst potential. Failed guard heaters precluded further testing. The SOFC analytical basis for the baseline system was validated with experimental data. Two system configurations that utilize a pressurized SOFC design with separated anode and cathode streams were analyzed. System efficiencies greater than 60% were predicted when integrating the separated anode and cathode stream module configuration with a high efficiency catalytic gasifier.

  20. Development of a Fish Cell Biosensor System for Genotoxicity Detection Based on DNA Damage-Induced Trans-Activation of p21 Gene Expression

    Directory of Open Access Journals (Sweden)

    Huarong Guo

    2012-09-01

    Full Text Available p21CIP1/WAF1 is a p53-target gene in response to cellular DNA damage. Here we report the development of a fish cell biosensor system for high throughput genotoxicity detection of new drugs, by stably integrating two reporter plasmids of pGL3-p21-luc (human p21 promoter linked to firefly luciferase and pRL-CMV-luc (CMV promoter linked to Renilla luciferase into marine flatfish flounder gill (FG cells, referred to as p21FGLuc. Initial validation of this genotoxicity biosensor system showed that p21FGLuc cells had a wild-type p53 signaling pathway and responded positively to the challenge of both directly acting genotoxic agents (bleomycin and mitomycin C and indirectly acting genotoxic agents (cyclophosphamide with metabolic activation, but negatively to cyclophosphamide without metabolic activation and the non-genotoxic agents ethanol and D-mannitol, thus confirming a high specificity and sensitivity, fast and stable response to genotoxic agents for this easily maintained fish cell biosensor system. This system was especially useful in the genotoxicity detection of Di(2-ethylhexyl phthalate (DEHP, a rodent carcinogen, but negatively reported in most non-mammalian in vitro mutation assays, by providing a strong indication of genotoxicity for DEHP. A limitation for this biosensor system was that it might give false positive results in response to sodium butyrate and any other agents, which can trans-activate the p21 gene in a p53-independent manner.

  1. Possibility of application of solid oxide electrolysis cell on a smart iron-making process based on an active carbon recycling energy system

    International Nuclear Information System (INIS)

    Efficient carbon dioxide (CO2) reduction into carbon monoxide (CO) is required to establish a smart iron-making process based on an active carbon recycling energy system (iACRES). A disk-type solid oxide electrolysis cell (SOEC) was prepared and examined experimentally for application to the CO2 reduction process in iACRES. A SOEC with a cathode|electrolyte|anode structure of Ni-YSZ|YSZ|La0.6Sr0.4Co0.2Fe0.8O3-δ was fabricated. The electrolysis of carbon dioxide was conducted at 800-900°C. A current density of 107.1 mA cm-2 was measured between the cathode and anode at 900°C and at 2.52 V. The production rates of CO and O2 were in agreement with the theoretical values determined using Faraday's law. Evaluation of iACRES using the experimental results indicated that an estimated 0.73 high-temperature gas cooled reactor units as the primary energy source for CO2 reduction and a SOEC surface area of 0.098 km2 were required for the reduction of 30% CO2 in blast furnace gas emitted from a conventional blast furnace. (author)

  2. Improved biosensor-based detection system

    DEFF Research Database (Denmark)

    2015-01-01

    Described is a new biosensor-based detection system for effector compounds, useful for in vivo applications in e.g. screening and selecting of cells which produce a small molecule effector compound or which take up a small molecule effector compound from its environment. The detection system...... comprises a protein or RNA-based biosensor for the effector compound which indirectly regulates the expression of a reporter gene via two hybrid proteins, providing for fewer false signals or less 'noise', tuning of sensitivity or other advantages over conventional systems where the biosensor directly...

  3. Non-genetic engineering of cells for drug delivery and cell-based therapy.

    Science.gov (United States)

    Wang, Qun; Cheng, Hao; Peng, Haisheng; Zhou, Hao; Li, Peter Y; Langer, Robert

    2015-08-30

    Cell-based therapy is a promising modality to address many unmet medical needs. In addition to genetic engineering, material-based, biochemical, and physical science-based approaches have emerged as novel approaches to modify cells. Non-genetic engineering of cells has been applied in delivering therapeutics to tissues, homing of cells to the bone marrow or inflammatory tissues, cancer imaging, immunotherapy, and remotely controlling cellular functions. This new strategy has unique advantages in disease therapy and is complementary to existing gene-based cell engineering approaches. A better understanding of cellular systems and different engineering methods will allow us to better exploit engineered cells in biomedicine. Here, we review non-genetic cell engineering techniques and applications of engineered cells, discuss the pros and cons of different methods, and provide our perspectives on future research directions.

  4. Neural Network-Based Modeling of PEM fuel cell and Controller Synthesis of a stand-alone system for residential application

    Directory of Open Access Journals (Sweden)

    Khaled Mammar

    2012-11-01

    Full Text Available The paper is focused especially on presenting possibilities of applying artificial neural networks at creating the optimal model PEM fuel cell. Various ANN approaches have been tested; the back-propagation feed-forward networks show satisfactory performance with regard to cell voltage prediction. The model is then used in a power system for residential application. This models include an ANN fuel cell stack model, reformer model and DC/AC inverter model. Furthermore a neural network (NNTC and fuzzy logic (FLC controllers are used to control active power of PEM fuel cell system. The controllers modifies the hydrogen flow feedback from the terminal load. The validity of the controller is verified when the fuel cell system model is used in conjunction with the NNT controller to predict the response of the active power to: (a computer-simulated step changes in the load active and reactive power demand, and (b actual active and reactive load demand of a single family residence. Simulation results confirmed the high performance capability of the neural network (NNTC to control power generation.

  5. Battery Cell Balancing System and Method

    Science.gov (United States)

    Davies, Francis J. (Inventor)

    2014-01-01

    A battery cell balancing system is operable to utilize a relatively small number of transformers interconnected with a battery having a plurality of battery cells to selectively charge the battery cells. Windings of the transformers are simultaneously driven with a plurality of waveforms whereupon selected battery cells or groups of cells are selected and charged. A transformer drive circuit is operable to selectively vary the waveforms to thereby vary a weighted voltage associated with each of the battery cells.

  6. Efficient anti-Prelog enantioselective reduction of acetyltrimethylsilane to (R-1-trimethylsilylethanol by immobilized Candida parapsilosis CCTCC M203011 cells in ionic liquid-based biphasic systems

    Directory of Open Access Journals (Sweden)

    Zhang Bo-Bo

    2012-08-01

    Full Text Available Abstract Background Biocatalytic asymmetric reductions with whole cells can offer high enantioselectivity, environmentally benign processes and energy-effective operations and thus are of great interest. The application of whole cell-mediated bioreduction is often restricted if substrate and product have low water solubility and/or high toxicity to the biocatalyst. Many studies have shown that a biphasic system is often useful in this instance. Hence, we developed efficient biphasic reaction systems with biocompatible water-immiscible ionic liquids (ILs, to improve the biocatalytic anti-Prelog enantioselective reduction of acetyltrimethylsilane (ATMS to (R-1-trimethylsilylethanol {(R-1-TMSE}, which is key synthon for a large number of silicon-containing drugs, using immobilized Candida parapsilosis CCTCC M203011 cells as the biocatalyst. Results It was found that the substrate ATMS and the product 1-TMSE exerted pronounced toxicity to immobilized Candida parapsilosis CCTCC M203011 cells. The biocompatible water-immiscible ILs can be applied as a substrate reservoir and in situ extractant for the product, thus greatly enhancing the efficiency of the biocatalytic process and the operational stability of the cells as compared to the IL-free aqueous system. Various ILs exerted significant but different effects on the bioreduction and the performances of biocatalysts were closely related to the kinds and combination of cation and anion of ILs. Among all the water-immiscible ILs investigated, the best results were observed in 1-butyl-3-methylimidazolium hexafluorophosphate (C4mim·PF6/buffer biphasic system. Furthermore, it was shown that the optimum substrate concentration, volume ratio of buffer to IL, buffer pH, reaction temperature and shaking rate for the bioreduction were 120 mM, 8/1 (v/v, 6.0, 30°C and 180 r/min, respectively. Under these optimized conditions, the initial reaction rate, the maximum yield and the product e.e. were 8.1

  7. Distributed event-based systems

    CERN Document Server

    Fiege, Ludger; Pietzuch, Peter R

    2006-01-01

    This book provides an in-depth description of event-based systems, covering topics ranging from local event matching and distributed event forwarding algorithms, through a practical discussion of software engineering issues raised by the event-based style, to state-of-the-art research in event-based systems like composite event detection and security. The authors offer a comprehensive overview, and show the power of event-based architectures in modern system design, encouraging professionals to exploit this technique in next generation large-scale distributed applications like information diss

  8. Web-based support systems

    CERN Document Server

    Yao, JingTao

    2010-01-01

    The emerging interdisciplinary study of Web-based support systems focuses on the theories, technologies and tools for the design and implementation of Web-based systems that support various human activities. This book presents the state-of-the-art in Web-based support systems (WSS). The research on WSS is multidisciplinary and focuses on supporting various human activities in different domains/fields based on computer science, information technology, and Web technology. The main goal is to take the opportunities of the Web, to meet the challenges of the Web, to extend the human physical limita

  9. Modular PEM Fuel Cell SCADA & Simulator System

    Directory of Open Access Journals (Sweden)

    Francisca Segura

    2015-09-01

    Full Text Available The paper presents a Supervision, Control, Data Acquisition and Simulation (SCADA & Simulator system that allows for real-time training in the actual operation of a modular PEM fuel cell system. This SCADA & Simulator system consists of a free software tool that operates in real time and simulates real situations like failures and breakdowns in the system. This developed SCADA & Simulator system allows us to properly operate a fuel cell and helps us to understand how fuel cells operate and what devices are needed to configure and run the fuel cells, from the individual stack up to the whole fuel cell system. The SCADA & Simulator system governs a modular system integrated by three PEM fuel cells achieving power rates higher than tens of kilowatts.

  10. Mesenchymal Stem Cell-Based Therapy

    OpenAIRE

    Mundra, Vaibhav; Gerling, Ivan C.; Mahato, Ram I.

    2012-01-01

    Mesenchymal stem cells (MSCs) are multipotent adult stem cells which have self-renewal capacity and differentiation potential into several mesenchymal lineages including bones, cartilages, adipose tissues and tendons. MSCs may repair tissue injuries and prevent immune cell activation and proliferation. Immunomodulation and secretion of growth factors by MSCs have led to realizing the true potential of MSC-based cell therapy. The use of MSCs as immunomdulators has been explored in cell/organ t...

  11. Expert and Knowledge Based Systems.

    Science.gov (United States)

    Demaid, Adrian; Edwards, Lyndon

    1987-01-01

    Discusses the nature and current state of knowledge-based systems and expert systems. Describes an expert system from the viewpoints of a computer programmer and an applications expert. Addresses concerns related to materials selection and forecasts future developments in the teaching of materials engineering. (ML)

  12. MTA Computer Based Evaluation System.

    Science.gov (United States)

    Brenner, Lisa P.; And Others

    The MTA PLATO-based evaluation system, which has been implemented by a consortium of schools of medical technology, is designed to be general-purpose, modular, data-driven, and interactive, and to accommodate other national and local item banks. The system provides a comprehensive interactive item-banking system in conjunction with online student…

  13. Automated microscopy system for peripheral blood cells

    Science.gov (United States)

    Boev, Sergei F.; Sazonov, Vladimir V.; Kozinets, Gennady I.; Pogorelov, Valery M.; Gusev, Alexander A.; Korobova, Farida V.; Vinogradov, Alexander G.; Verdenskaya, Natalya V.; Ivanova, Irina A.

    2000-11-01

    The report describes the instrument ASPBS (Automated Screening of Peripheral Blood Cells) designed for an automated analysis of dry blood smears. The instrument is based on computer microscopy and uses dry blood smears prepared according to the standard Romanovskii-Giemza procedure. In comparison with the well-known flow cytometry systems, our instrument provides more detailed information and offers an opporunity of visualizing final results. The basic performances of the instrument are given. Software of this instrument is based on digital image processing and image recognition procedures. It is pointed out that the instrument can be used as a fairly universal tool in scientific research, public demonstrations, in medical treatment, and in medical education. The principle used as the basis of the instrument appeared adequate for creating an instrument version serviceable even during space flights where standard manual procedures and flow cytometry systems fail. The benefit of the use of the instrument in clinical laboratories is described.

  14. Solid Oxide Fuel Cell Systems PVL Line

    Energy Technology Data Exchange (ETDEWEB)

    Susan Shearer - Stark State College; Gregory Rush - Rolls-Royce Fuel Cell Systems

    2012-05-01

    In July 2010, Stark State College (SSC), received Grant DE-EE0003229 from the U.S. Department of Energy (DOE), Golden Field Office, for the development of the electrical and control systems, and mechanical commissioning of a unique 20kW scale high-pressure, high temperature, natural gas fueled Stack Block Test System (SBTS). SSC worked closely with subcontractor, Rolls-Royce Fuel Cell Systems (US) Inc. (RRFCS) over a 13 month period to successfully complete the project activities. This system will be utilized by RRFCS for pre-commercial technology development and training of SSC student interns. In the longer term, when RRFCS is producing commercial products, SSC will utilize the equipment for workforce training. In addition to DOE Hydrogen, Fuel Cells, and Infrastructure Technologies program funding, RRFCS internal funds, funds from the state of Ohio, and funding from the DOE Solid State Energy Conversion Alliance (SECA) program have been utilized to design, develop and commission this equipment. Construction of the SBTS (mechanical components) was performed under a Grant from the State of Ohio through Ohio's Third Frontier program (Grant TECH 08-053). This Ohio program supported development of a system that uses natural gas as a fuel. Funding was provided under the Department of Energy (DOE) Solid-state Energy Conversion Alliance (SECA) program for modifications required to test on coal synthesis gas. The subject DOE program provided funding for the electrical build, control system development and mechanical commissioning. Performance testing, which includes electrical commissioning, was subsequently performed under the DOE SECA program. Rolls-Royce Fuel Cell Systems is developing a megawatt-scale solid oxide fuel cell (SOFC) stationary power generation system. This system, based on RRFCS proprietary technology, is fueled with natural gas, and operates at elevated pressure. A critical success factor for development of the full scale system is the capability

  15. Accelerated killing of cancer cells using a multifunctional single-walled carbon nanotube-based system for targeted drug delivery in combination with photothermal therapy

    Directory of Open Access Journals (Sweden)

    Jeyamohan P

    2013-07-01

    Full Text Available Prashanti Jeyamohan, Takashi Hasumura, Yutaka Nagaoka, Yasuhiko Yoshida, Toru Maekawa, D Sakthi Kumar Bio-Nano Electronics Research Centre, Graduate School of Interdisciplinary New Science, Toyo University, Kawagoe, Japan Abstract: The photothermal effect of single-walled carbon nanotubes (SWCNTs in combination with the anticancer drug doxorubicin (DOX for targeting and accelerated destruction of breast cancer cells is demonstrated in this paper. A targeted drug-delivery system was developed for selective killing of breast cancer cells with polyethylene glycol biofunctionalized and DOX-loaded SWCNTs conjugated with folic acid. In our work, in vitro drug-release studies showed that the drug (DOX binds at physiological pH (pH 7.4 and is released only at a lower pH, ie, lysosomal pH (pH 4.0, which is the characteristic pH of the tumor environment. A sustained release of DOX from the SWCNTs was observed for a period of 3 days. SWCNTs have strong optical absorbance in the near-infrared (NIR region. In this special spectral window, biological systems are highly transparent. Our study reports that under laser irradiation at 800 nm, SWCNTs exhibited strong light–heat transfer characteristics. These optical properties of SWCNTs open the way for selective photothermal ablation in cancer therapy. It was also observed that internalization and uptake of folate-conjugated NTs into cancer cells was achieved by a receptor-mediated endocytosis mechanism. Results of the in vitro experiments show that laser was effective in destroying the cancer cells, while sparing the normal cells. When the above laser effect was combined with DOX-conjugated SWCNTs, we found enhanced and accelerated killing of breast cancer cells. Thus, this nanodrug-delivery system, consisting of laser, drug, and SWCNTs, looks to be a promising selective modality with high treatment efficacy and low side effects for cancer therapy. Keywords: cancer, nanotherapy, SWCNTs, targeted drug delivery

  16. Cell-Based Biosensors Principles and Applications

    CERN Document Server

    Wang, Ping

    2009-01-01

    Written by recognized experts the field, this leading-edge resource is the first book to systematically introduce the concept, technology, and development of cell-based biosensors. You find details on the latest cell-based biosensor models and novel micro-structure biosensor techniques. Taking an interdisciplinary approach, this unique volume presents the latest innovative applications of cell-based biosensors in a variety of biomedical fields. The book also explores future trends of cell-based biosensors, including integrated chips, nanotechnology and microfluidics. Over 140 illustrations hel

  17. Development of JFH1-based cell culture systems for hepatitis C virus genotype 4a and evidence for cross-genotype neutralization

    DEFF Research Database (Denmark)

    Scheel, Troels Kasper Høyer; Gottwein, Judith Margarete; Jensen, Tina Birk;

    2008-01-01

    of NS2 of the 4a prototype strain ED43 that, after transfection of Huh7.5 cells with RNA transcripts, produced infectious viruses. Compared with the J6/JFH control virus, production of viruses was delayed. However, efficient spread of infection and high HCV RNA and infectivity titers were obtained...... in serial passages. Sequence analysis of recovered viruses and subsequent reverse genetic studies revealed a vital dependence on one or two NS2 mutations, depending on the 4a/2a junction. Infectivity of ED43/JFH1 viruses was CD81 dependent. The genotype 4 cell culture systems permit functional analyses...

  18. Avicequinone C Isolated from Avicennia marina Exhibits 5α-Reductase-Type 1 Inhibitory Activity Using an Androgenic Alopecia Relevant Cell-Based Assay System

    OpenAIRE

    Ruchy Jain; Orawan Monthakantirat; Parkpoom Tengamnuay; Wanchai De-Eknamkul

    2014-01-01

    Avicennia marina (AM) exhibits various biological activities and has been traditionally used in Egypt to cure skin diseases. In this study, the methanolic heartwood extract of AM was evaluated for inhibitory activity against 5α-reductase (5α-R) [E.C.1.3.99.5], the enzyme responsible for the over-production of 5α-dihydrotestosterone (5α-DHT) causing androgenic alopecia (AGA). An AGA-relevant cell-based assay was developed using human hair dermal papilla cells (HHDPCs), the main regulator of ha...

  19. Break-in and Performance Issues on a single cell PBI-based PEM Fuel Cell

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen; Jespersen, Jesper Lebæk

    Depending on the application in question and the load cycle of operation, fuel cell degradation can be a serious problem. Fuel cell degradation of PBI-based MEA's and fuel cells in general is quite complex. The rate of degradation depends on several parameters, where the operating temperature...... and the current drawn from the fuel cell are of great importance. One must therefore choose the point of operation carefully in order for the fuel cell to fulfil the requirements for lifetime perform-ance of the system. Break-in of fuel cells is often done in scientific experiments to improve the performance...... of the fuel cell, even though break-in of a fuel cell implemented in a commercial application would most likely not be feasible. In the present work a commercially available PBI-based high temperature MEA is subject to a break-in procedure, as specified by the manufacturer. The cell was operated at 160 °C...

  20. System Studies of Fuel Cell Power Plants

    OpenAIRE

    Kivisaari, Timo

    2001-01-01

    This thesis concerns system studies of power plants wheredifferent types of fuel cells accomplish most of the energyconversion. Ever since William Grove observed the fuel cell effect inthe late 1830s fuel cells have been the subject or more or lessintense research and development. Especially in the USA theseactivities intensified during the second part of the 1950s,resulting in the development of the fuel cells used in theApollo-program. Swedish fuel cell activities started in themid-1960s, w...

  1. Content Based Video Retrieval Systems

    Directory of Open Access Journals (Sweden)

    B V Patel

    2012-05-01

    Full Text Available With the development of multimedia data types and available bandwidth there is huge demand of video retrieval systems, as users shift from text based retrieval systems to content based retrieval systems. Selection of extracted features play an important role in content based video retrieval regardless of video attributes being under consideration. These features are intended for selecting, indexing and ranking according to their potential interest to the user. Good features selection also allows the time and space costs of the retrieval process to be reduced. This survey reviews the interesting features that can beextracted from video data for indexing and retrieval along with similarity measurement methods. We also identify present research issues in area of content based video retrieval systems.

  2. A Novel Health Information Technology Communication System to Increase Caregiver Activation in the Context of Hospital-Based Pediatric Hematopoietic Cell Transplantation: A Pilot Study

    OpenAIRE

    Maher, Molly; Hanauer, David A.; Kaziunas, Elizabeth; Ackerman, Mark S.; Derry, Holly; Forringer, Rachel; Miller, Kristen; O'Reilly, Dennis; An, Lawrence; Tewari, Muneesh; Choi, Sung Won

    2015-01-01

    Background Pediatric hematopoietic cell transplantation (HCT), commonly referred to as blood and marrow transplantation (BMT), is an intense treatment modality that requires the involvement of engaged caregivers during the patient’s (child’s) prolonged hospitalization. The ubiquity of electronic health records (EHRs) and a trend toward patient-centered care could allow a novel health information technology (IT) system to increase parental engagement. The paucity of research on acute care, hos...

  3. Efficiency enhancement in dye sensitized solar cells using gel polymer electrolytes based on a tetrahexylammonium iodide and MgI2 binary iodide system.

    Science.gov (United States)

    Bandara, T M W J; Dissanayake, M A K L; Jayasundara, W J M J S R; Albinsson, I; Mellander, B-E

    2012-06-28

    Quasi-solid-state dye-sensitized solar cells have drawn the attention of scientists and technologists as a potential candidate to supplement future energy needs. The conduction of iodide ions in quasi-solid-state polymer electrolytes and the performance of dye sensitized solar cells containing such electrolytes can be enhanced by incorporating iodides having appropriate cations. Gel-type electrolytes, based on PAN host polymers and mixture of salts tetrahexylammonium iodide (Hex4N(+)I(-)) and MgI2, were prepared by incorporating ethylene carbonate and propylene carbonate as plasticizers. The salt composition in the binary mixture was varied in order to optimize the performance of solar cells. The electrolyte containing 120% Hex4N(+)I(-) with respect to weight of PAN and without MgI2 showed the highest conductivity out of the compositions studied, 2.5 × 10(-3) S cm(-1) at 25 °C, and a glass transition at -102.4 °C. However, the electrolyte containing 100% Hex4N(+)I(-) and 20% MgI2 showed the best solar cell performance highlighting the influence of the cation on the performance of the cell. The predominantly ionic behaviour of the electrolytes was established from the dc polarization data and all the electrolytes exhibit iodide ion transport. Seven different solar cells were fabricated employing different electrolyte compositions. The best cell using the electrolyte with 100% Hex4N(+)I(-) and 20% MgI2 with respect to PAN weight showed 3.5% energy conversion efficiency and 8.6 mA cm(-2) short circuit current density.

  4. Analysis and Design of Bi-Directional DC-DC Converter in the Extended Run Time DC UPS System Based on Fuel Cell and Supercapacitor

    DEFF Research Database (Denmark)

    Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.;

    2009-01-01

    Abstract-In this paper, an extended run time DC UPS system structure with fuel cell and supercapacitor is investigated. A wide input range bi-directional dc-dc converter is described along with the phase-shift modulation scheme and phase-shift with duty cycle control, in different modes...... input voltage combined with load current feedback using PI controller with anti-windup scheme to realize closed-loop control of the whole system, and verify the feasibility of the control scheme proposed by simulation. A 1kW prototype controlled by TMS320F2808 DSP is implemented and tested. Experimental...

  5. 基于学习元平台的微课设计%Design of Micro-lecture Based on Learning Cell System

    Institute of Scientific and Technical Information of China (English)

    余胜泉; 陈敏

    2014-01-01

    微课已成为当前教育领域研究的一大热点,受到越来越多学者的关注。本文通过微课的各种定义,分析了微课认识的误区,指出微课的本质是“课”,并从“课”的角度提出,微课是在微型资源的基础上附加教学服务的小型化课程,由微型资源、学习活动、学习评价和认证服务四部分构成。此外,由于微课小而散,应通过语义技术描述微课间的整体知识逻辑,实现散而有序。在此基础之上,本文介绍了基于学习元的微课设计思路,包括微课设计、教学信息描述、微课聚合和开发模式等,试图为研究者和设计者们提供参考。%Micro-lecture has become a hot research point in education,which attracts more and more attention from scholars. This paper analyzes the current various definitions of micro-lecture, revealing people's misunderstanding of micro-lecture, pointing out that the nature of micro-lecture is"lesson". From this point, micro-lecture is micro-les-son based on micro-resources with additional teaching service,which consists of four parts: micro resources, learning activities, learning assessment and certification services. Besides, micro-lecture is small and scattered, so the overall knowledge logic between micro-lectures should be described by semantic technology to keep micro-lecture organized. On this basis, this paper gives the introduction to micro-lecture design based on learning cell system, including micro-lecture planning, teaching information description, micro-lecture aggregation and development patterns,etc. , trying to provide ideas and reference for micro-lecture researchers and designers.

  6. Nanowire-based All Oxide Solar Cells

    OpenAIRE

    Yang, Peidong

    2009-01-01

    We present an all-oxide solar cell fabricated from vertically oriented zinc oxide nanowires and cuprous oxide nanoparticles. Our solar cell consists of vertically oriented n-type zinc oxide nanowires, surrounded by a film constructed from p-type cuprous oxide nanoparticles. Our solution-based synthesis of inexpensive and environmentally benign oxide materials in a solar cell would allow for the facile production of large-scale photovoltaic devices. We found that the solar cell performance is ...

  7. Web based Measurement System for Solar Radiation

    Directory of Open Access Journals (Sweden)

    Shachi Awasthi

    2012-06-01

    Full Text Available We present in this paper, the principles of the measurement system for solar radiation, and our implementation using Web based data logging concept. The photocurrent produced by Silicon PN junction is used as a solar radiation transducer, to make it more viable we have used commercially available solar panels as our transducers. Using a silicon solar cell as sensor, a low cost solar radiometer can be constructed. The photocurrent produced by solar cell is electronically tailored to be measured and stored by our web based data acquisition and monitoring system. Measurement using real solar cell array gives a good measure of actual producible energy by solar arrays. Our portable instrument can be used in remote sites and substitutes the solar monitor and integrator, Current data of solar radiation can be monitored using Ethernet interface available in all PC, Laptops. We store the data into a secure digital card which can be retrieved to plot and analyse the data. We have developed system hardware and software based on ATmega32 AVR Microcontrollers and ENC28J60 Ethernet PHY and MAC network interface chip by Microchip. So the global irradiance data are obtained after correction using the instantaneous measurement of ambient temperature which allows us to calculate the junction temperature and consequently improve the precision of measurement of our data acquisition system.

  8. Web based Measurement System for Solar Radiation

    Directory of Open Access Journals (Sweden)

    Shachi Awasthi

    2012-06-01

    Full Text Available We present in this paper, the principles of themeasurement system for solar radiation, and ourimplementation using Web based data loggingconcept.The photocurrent produced by Silicon PNjunction is used as a solar radiation transducer, tomake it more viable we have used commerciallyavailable solar panels as our transducers. Using asilicon solar cell as sensor, a low cost solarradiometer can be constructed. The photocurrentproduced by solar cell is electronically tailored to bemeasured and stored by our web based dataacquisition and monitoring system. Measurementusing real solar cell array gives a good measure ofactual producible energy by solar arrays. Ourportable instrument can be used in remote sites andsubstitutes the solar monitor and integrator,Current data of solar radiation can be monitoredusing Ethernet interface available in all PC,Laptops. We store the data into a secure digital cardwhich can be retrieved to plot and analyse the data.We have developed system hardware andsoftware based on ATmega32 AVR Microcontrollersand ENC28J60 Ethernet PHY and MAC networkinterface chip by Microchip.So the global irradiance data are obtained aftercorrection using the instantaneous measurement ofambient temperature which allows us to calculatethe junction temperature and consequently improvethe precision of measurement of our dataacquisition system

  9. Biotoxin Detection Using Cell-Based Sensors

    OpenAIRE

    Pratik Banerjee; Spyridon Kintzios; Balabhaskar Prabhakarpandian

    2013-01-01

    Cell-based biosensors (CBBs) utilize the principles of cell-based assays (CBAs) by employing living cells for detection of different analytes from environment, food, clinical, or other sources. For toxin detection, CBBs are emerging as unique alternatives to other analytical methods. The main advantage of using CBBs for probing biotoxins and toxic agents is that CBBs respond to the toxic exposures in the manner related to actual physiologic responses of the vulnerable subjects. The results ob...

  10. Spectrin-based skeleton as an actor in cell signaling.

    Science.gov (United States)

    Machnicka, B; Grochowalska, R; Bogusławska, D M; Sikorski, A F; Lecomte, M C

    2012-01-01

    This review focuses on the recent advances in functions of spectrins in non-erythroid cells. We discuss new data concerning the commonly known role of the spectrin-based skeleton in control of membrane organization, stability and shape, and tethering protein mosaics to the cellular motors and to all major filament systems. Particular effort has been undertaken to highlight recent advances linking spectrin to cell signaling phenomena and its participation in signal transduction pathways in many cell types.

  11. Mesenchymal stem cell recruitment by stromal derived factor-1-delivery systems based on chitosan/poly(γ-glutamic acid polyelectrolyte complexes

    Directory of Open Access Journals (Sweden)

    RM Gonçalves

    2012-04-01

    Full Text Available Human mesenchymal stem cells (hMSCs have an enormous potential for tissue engineering and cell-based therapies. With a potential of differentiation into multiple lineages and immune-suppression, these cells play a key role in tissue remodelling and regeneration.Here a method of hMSC recruitment is described, based on the incorporation of a chemokine in Chitosan (Ch/Poly(γ-glutamic acid (γ-PGA complexes. Ch is a non-toxic, cationic polysaccharide widely investigated. γ-PGA is a hydrophilic, non-toxic, biodegradable and negatively charged poly-amino acid. Ch and γ-PGA, being oppositely charged, can be combined through electrostatic interactions. These biocompatible structures can be used as carriers for active substances and can be easily modulated in order to control the delivery of drugs, proteins, DNA, etc.Using the layer-by-layer method, Ch and γ-PGA were assembled into polyelectrolyte multilayers films (PEMs with thickness of 120 nm. The chemokine stromal-derived factor-1 (SDF-1 was incorporated in these complexes and was continuously released during 120 h. The method of SDF-1 incorporation is of crucial importance for polymers assembly into PEMs and for the release kinetics of this chemokine. The Ch/γ-PGA PEMs with SDF-1 were able to recruit hMSCs, increasing the cell migration up to 6 fold to a maximum of 16.2 ± 4.9 cells/mm2. The controlled release of SDF-1 would be of great therapeutic value in the process of hMSC homing to injured tissues. This is the first study suggesting Ch/γ-PGA PEMs as SDF-1 reservoirs to recruit hMSCs, describing an efficient method of chemokine incorporation that allows a sustained released up to 5 days and that can be easily scaled-up.

  12. Solar based hydrogen production systems

    CERN Document Server

    Dincer, Ibrahim

    2013-01-01

    This book provides a comprehensive analysis of various solar based hydrogen production systems. The book covers first-law (energy based) and second-law (exergy based) efficiencies and provides a comprehensive understanding of their implications. It will help minimize the widespread misuse of efficiencies among students and researchers in energy field by using an intuitive and unified approach for defining efficiencies. The book gives a clear understanding of the sustainability and environmental impact analysis of the above systems. The book will be particularly useful for a clear understanding

  13. Environmental tests of metallization systems for terrestrial photovoltaic cells

    Science.gov (United States)

    Alexander, P., Jr.

    1985-01-01

    Seven different solar cell metallization systems were subjected to temperature cycling tests and humidity tests. Temperature cycling excursions were -50 deg C to 150 deg C per cycle. Humidity conditions were 70 deg C at 98% relative humidity. The seven metallization systems were: Ti/Ag, Ti/Pd/Ag, Ti/Pd/Cu, Ni/Cu, Pd/Ni/Solder, Cr/Pd/Ag, and thick film Ag. All metallization systems showed a slight to moderate decrease in cell efficiencies after subjection to 1000 temperature cycles. Six of the seven metallization systems also evidenced slight increases in cell efficiencies after moderate numbers of cycles, generally less than 100 cycles. The copper based systems showed the largest decrease in cell efficiencies after temperature cycling. All metallization systems showed moderate to large decreases in cell efficiencies after 123 days of humidity exposure. The copper based systems again showed the largest decrease in cell efficiencies after humidity exposure. Graphs of the environmental exposures versus cell efficiencies are presented for each metallization system, as well as environmental exposures versus fill factors or series resistance.

  14. TOPICAL REVIEW: Stem cells engineering for cell-based therapy

    Science.gov (United States)

    Taupin, Philippe

    2007-09-01

    Stem cells carry the promise to cure a broad range of diseases and injuries, from diabetes, heart and muscular diseases, to neurological diseases, disorders and injuries. Significant progresses have been made in stem cell research over the past decade; the derivation of embryonic stem cells (ESCs) from human tissues, the development of cloning technology by somatic cell nuclear transfer (SCNT) and the confirmation that neurogenesis occurs in the adult mammalian brain and that neural stem cells (NSCs) reside in the adult central nervous system (CNS), including that of humans. Despite these advances, there may be decades before stem cell research will translate into therapy. Stem cell research is also subject to ethical and political debates, controversies and legislation, which slow its progress. Cell engineering has proven successful in bringing genetic research to therapy. In this review, I will review, in two examples, how investigators are applying cell engineering to stem cell biology to circumvent stem cells' ethical and political constraints and bolster stem cell research and therapy.

  15. Immunity Based Worm Detection System

    Institute of Scientific and Technical Information of China (English)

    HONG Zheng; WU Li-fa; WANG Yuan-yuan

    2007-01-01

    Current worm detection methods are unable to detect multi-vector polymorphic worms effectively.Based on negative selection mechanism of the immune system,a local network worm detection system that detects worms was proposed.Normal network service requests were represented by self-strings,and the detection system used self-strings to monitor the network for anomaly.According to the properties of worm propagation,a control center correlated the anomalies detected in the form of binary trees to ensure the accuracy of worm detection.Experiments show the system to be effective in detecting the traditional as well as multi-vector polymorphic worms.

  16. Modelling of robotic work cells using agent based-approach

    Science.gov (United States)

    Sękala, A.; Banaś, W.; Gwiazda, A.; Monica, Z.; Kost, G.; Hryniewicz, P.

    2016-08-01

    In the case of modern manufacturing systems the requirements, both according the scope and according characteristics of technical procedures are dynamically changing. This results in production system organization inability to keep up with changes in a market demand. Accordingly, there is a need for new design methods, characterized, on the one hand with a high efficiency and on the other with the adequate level of the generated organizational solutions. One of the tools that could be used for this purpose is the concept of agent systems. These systems are the tools of artificial intelligence. They allow assigning to agents the proper domains of procedures and knowledge so that they represent in a self-organizing system of an agent environment, components of a real system. The agent-based system for modelling robotic work cell should be designed taking into consideration many limitations considered with the characteristic of this production unit. It is possible to distinguish some grouped of structural components that constitute such a system. This confirms the structural complexity of a work cell as a specific production system. So it is necessary to develop agents depicting various aspects of the work cell structure. The main groups of agents that are used to model a robotic work cell should at least include next pattern representatives: machine tool agents, auxiliary equipment agents, robots agents, transport equipment agents, organizational agents as well as data and knowledge bases agents. In this way it is possible to create the holarchy of the agent-based system.

  17. Innovative High Temperature Fuel Cell systems

    NARCIS (Netherlands)

    Au, Siu Fai

    2003-01-01

    The world's energy consumption is growing extremely rapidly. Fuel cell systems are of interest by researchers and industry as the more efficient alternative to conventional thermal systems for power generation. The principle of fuel cell conversion does not involve thermal combustion and hence in th

  18. Fullerene based organic solar cells

    NARCIS (Netherlands)

    Popescu, Lacramioara Mihaela

    2008-01-01

    The direct conversion of the sunlight into electricity is the most elegant process to generate environmentally-friendly renewable energy. Plastic solar cells offer the prospect of flexible, lightweight, lower cost of manufacturing, and hopefully an efficient way to produce electricity from sunlight.

  19. Baculovirus integration with the vertebrate cells in system in vitro

    Directory of Open Access Journals (Sweden)

    Strokovskaya L. I.

    2010-11-01

    Full Text Available In this review the literature data are analyzed relative to the study of a new vector system for the cells of vertebrates, based on the insect viruses – baculoviruses. The ways and mechanisms of recombinant baculoviruses penetration into cells, the factors, which influence the effectiveness of transduction, the principles of the modification of virus display, and the reaction of the different types of cells on virus introduction are examined. The prospects of using recombinant baculoviruses in cellular engineering are discussed.

  20. NOD/scid IL-2Rgnull mice: a preclinical model system to evaluate human dendritic cell-based vaccine strategies in vivo

    Directory of Open Access Journals (Sweden)

    Spranger Stefani

    2012-02-01

    Full Text Available Abstract Background To date very few systems have been described for preclinical investigations of human cellular therapeutics in vivo. However, the ability to carry out comparisons of new cellular vaccines in vivo would be of substantial interest for design of clinical studies. Here we describe a humanized mouse model to assess the efficacy of various human dendritic cell (DC preparations. Two reconstitution regimes of NOD/scid IL2Rgnull (NSG mice with adult human peripheral blood mononuclear cells (PBMC were evaluated for engraftment using 4-week and 9-week schedules. This led to selection of a simple and rapid protocol for engraftment and vaccine evaluation that encompassed 4 weeks. Methods NSG recipients of human PBMC were engrafted over 14 days and then vaccinated twice with autologous DC via intravenous injection. Three DC vaccine formulations were compared that varied generation time in vitro (3 days versus 7 days and signals for maturation (with or without Toll-like receptor (TLR3 and TLR7/8 agonists using MART-1 as a surrogate antigen, by electroporating mature DC with in vitro transcribed RNA encoding full length protein. After two weekly vaccinations, the splenocyte populations containing human lymphocytes were recovered 7 days later and assessed for MART-1-specific immune responses using MHC-multimer-binding assays and functional assessment of specific killing of melanoma tumor cell lines. Results Human monocyte-derived DC generated in vitro in 3 days induced better MART-1-specific immune responses in the autologous donor T cells present in the humanized NSG mice. Moreover, consistent with our in vitro observations, vaccination using mature DC activated with TLR3 and TLR7/8 agonists resulted in enhanced immune responses in vivo. These findings led to a ranking of the DC vaccine effects in vivo that reflected the hierarchy previously found for these mature DC variations in vitro. Conclusions This humanized mouse model system enables

  1. 基于三结太阳电池的透射率测量系统%Transmittance measurement system based on triple-junction solar cells

    Institute of Scientific and Technical Information of China (English)

    赵慧洁; 唐吾; 张颖; 张庆祥

    2012-01-01

    The degradation of solar cells' coatings in space environment will shorten space aircraft's fight life.So the research of the system which can measure the coatings transmittance's change is important.The transmittance measurement system was constructed by two triple-junction solar cells,one of which was covered with the glass sample and another was not.The triple-junction solar cells were used as detectors to measure solar flux.The photocurrent measurement circuits convert the photocurrent to analog volt,which will be multiplied and filtered.And the volt was translated to digital signal,which is transferred to the computer finally.The photocurrent signals of two triple-junction solar cells were acquired to calculate the overall transmittance in the solar cell responding spectrum,by using two channels comparing measurement method.The solar cells operation temperature was monitored by platinum-chip temperature sensors,in order to avoid measurement error which is induced by temperature change.The measurement relative error of system is about 0.1%,and the measurement uncertainty is less than 0.15%,which is proved by experiment.%在空间环境中太阳电池的涂层会发生退化,从而影响航天器的飞行寿命,因此研究能够测量涂层光学透射率变化的系统具有重要意义.使用三结太阳电池作为探测器接收光能量;设计光电流检测电路,对太阳电池输出电流进行电流-电压变换,放大,滤波和模数转换,最终输入上位机处理;运用双通道比对测量技术,比较有玻璃和无玻璃的三结太阳电池光电流测量值,计算出玻璃样片在三结太阳电池响应谱段内的整体透射率;使用热电阻传感器检测太阳电池工作温度以消除温度变化带来的误差.通过实验测得系统的测试相对误差约为0.1%,测量不确定度小于0.15%.

  2. Alkaline regenerative fuel cell systems for energy storage

    Science.gov (United States)

    Schubert, F. H.; Reid, M. A.; Martin, R. E.

    1981-01-01

    A description is presented of the results of a preliminary design study of a regenerative fuel cell energy storage system for application to future low-earth orbit space missions. The high energy density storage system is based on state-of-the-art alkaline electrolyte cell technology and incorporates dedicated fuel cell and electrolysis cell modules. In addition to providing energy storage, the system can provide hydrogen and oxygen for attitude control of the satellite and for life support. During the daylight portion of the orbit the electrolysis module uses power provided by the solar array to generate H2 and O2 from the product water produced by the fuel cell module. The fuel cell module supplies electrical power during the dark period of the orbit.

  3. A fully automated system for adherent cells microinjection.

    Science.gov (United States)

    Becattini, Gabriele; Mattos, Leonardo S; Caldwell, Darwin G

    2014-01-01

    This paper proposes an automated robotic system to perform cell microinjections to relieve human operators from this highly difficult and tedious manual procedure. The system, which uses commercial equipment currently found on most biomanipulation laboratories, consists of a multitask software framework combining computer vision and robotic control elements. The vision part features an injection pipette tracker and an automatic cell targeting system that is responsible for defining injection points within the contours of adherent cells in culture. The main challenge is the use of bright-field microscopy only, without the need for chemical markers normally employed to highlight the cells. Here, cells are identified and segmented using a threshold-based image processing technique working on defocused images. Fast and precise microinjection pipette positioning over the automatically defined targets is performed by a two-stage robotic system which achieves an average injection rate of 7.6 cells/min with a pipette positioning precision of 0.23 μm. The consistency of these microinjections and the performance of the visual targeting framework were experimentally evaluated using two cell lines (CHO-K1 and HEK) and over 500 cells. In these trials, the cells were automatically targeted and injected with a fluorescent marker, resulting in a correct cell detection rate of 87% and a successful marker delivery rate of 67.5%. These results demonstrate that the new system is capable of better performances than expert operators, highlighting its benefits and potential for large-scale application. PMID:24403406

  4. A fully automated system for adherent cells microinjection.

    Science.gov (United States)

    Becattini, Gabriele; Mattos, Leonardo S; Caldwell, Darwin G

    2014-01-01

    This paper proposes an automated robotic system to perform cell microinjections to relieve human operators from this highly difficult and tedious manual procedure. The system, which uses commercial equipment currently found on most biomanipulation laboratories, consists of a multitask software framework combining computer vision and robotic control elements. The vision part features an injection pipette tracker and an automatic cell targeting system that is responsible for defining injection points within the contours of adherent cells in culture. The main challenge is the use of bright-field microscopy only, without the need for chemical markers normally employed to highlight the cells. Here, cells are identified and segmented using a threshold-based image processing technique working on defocused images. Fast and precise microinjection pipette positioning over the automatically defined targets is performed by a two-stage robotic system which achieves an average injection rate of 7.6 cells/min with a pipette positioning precision of 0.23 μm. The consistency of these microinjections and the performance of the visual targeting framework were experimentally evaluated using two cell lines (CHO-K1 and HEK) and over 500 cells. In these trials, the cells were automatically targeted and injected with a fluorescent marker, resulting in a correct cell detection rate of 87% and a successful marker delivery rate of 67.5%. These results demonstrate that the new system is capable of better performances than expert operators, highlighting its benefits and potential for large-scale application.

  5. Creating a completely "cell-free" system for protein synthesis.

    Science.gov (United States)

    Smith, Mark Thomas; Bennett, Anthony M; Hunt, Jeremy M; Bundy, Bradley C

    2015-01-01

    Cell-free protein synthesis is a promising tool to take biotechnology outside of the cell. A cell-free approach provides distinct advantages over in vivo systems including open access to the reaction environment and direct control over all chemical components for facile optimization and synthetic biology integration. Promising applications of cell-free systems include portable diagnostics, biotherapeutics expression, rational protein engineering, and biocatalyst production. The highest yielding and most economical cell-free systems use an extract composed of the soluble component of lysed Escherichia coli. Although E. coli lysis can be highly efficient (>99.999%), one persistent challenge is that the extract remains contaminated with up to millions of cells per mL. In this work, we examine the potential of multiple decontamination strategies to further reduce or eliminate bacteria in cell-free systems. Two strategies, sterile filtration and lyophilization, effectively eliminate contaminating cells while maintaining the systems' protein synthesis capabilities. Lyophilization provides the additional benefit of long-term stability at storage above freezing. Technologies for personalized, portable medicine and diagnostics can be expanded based on these foundational sterilized and completely "cell-free" systems.

  6. A Comparison of Optimal Operation of a Residential Fuel Cell Co-Generation System Using Clustered Demand Patterns Based on Kullback-Leibler Divergence

    Directory of Open Access Journals (Sweden)

    Takumi Hasizume

    2013-01-01

    Full Text Available When evaluating residential energy systems like co-generation systems, hot water and electricity demand profiles are critical. In this paper, the authors aim to extract basic time-series demand patterns from two kinds of measured demand (electricity and domestic hot water, and also aim to reveal effective demand patterns for primary energy saving. Time-series demand data are categorized with a hierarchical clustering method using a statistical pseudo-distance, which is represented by the generalized Kullback-Leibler divergence of two Gaussian mixture distributions. The classified demand patterns are built using hierarchical clustering and then a comparison is made between the optimal operation of a polymer electrolyte membrane fuel cell co-generation system and the operation of a reference system (a conventional combination of a condensing gas boiler and electricity purchased from the grid using the appropriately built demand profiles. Our results show that basic demand patterns are extracted by the proposed method, and the heat-to-power ratio of demand, the amount of daily demand, and demand patterns affect the primary energy saving of the co-generation system.

  7. Development of an Expert System as a Diagnostic Support of Cervical Cancer in Atypical Glandular Cells, Based on Fuzzy Logics and Image Interpretation

    Directory of Open Access Journals (Sweden)

    Karem R. Domínguez Hernández

    2013-01-01

    Full Text Available Cervical cancer is the second largest cause of death among women worldwide. Nowadays, this disease is preventable and curable at low cost and low risk when an accurate diagnosis is done in due time, since it is the neoplasm with the highest prevention potential. This work describes the development of an expert system able to provide a diagnosis to cervical neoplasia (CN precursor injuries through the integration of fuzzy logics and image interpretation techniques. The key contribution of this research focuses on atypical cases, specifically on atypical glandular cells (AGC. The expert system consists of 3 phases: (1 risk diagnosis which consists of the interpretation of a patient’s clinical background and the risks for contracting CN according to specialists; (2 cytology images detection which consists of image interpretation (IM and the Bethesda system for cytology interpretation, and (3 determination of cancer precursor injuries which consists of in retrieving the information from the prior phases and integrating the expert system by means of a fuzzy logics (FL model. During the validation stage of the system, 21 already diagnosed cases were tested with a positive correlation in which 100% effectiveness was obtained. The main contribution of this work relies on the reduction of false positives and false negatives by providing a more accurate diagnosis for CN.

  8. Thermodynamic analysis of a new combined cooling, heat and power system driven by solid oxide fuel cell based on ammonia-water mixture

    Science.gov (United States)

    Ma, Shaolin; Wang, Jiangfeng; Yan, Zhequan; Dai, Yiping; Lu, Bingheng

    2011-10-01

    Although a solid oxide fuel cell combined with a gas turbine (SOFC-GT) has good performance, the temperature of exhaust from gas turbine is still relatively high. In order to recover the waste heat of exhaust from the SOFC-GT to enhance energy conversion efficiency as well as to reduce the emissions of greenhouse gases and pollutants, in this study a new combined cooling, heat and power (CCHP) system driven by the SOFC is proposed to perform the trigeneration by using ammonia-water mixture to recover the waste heat of exhaust from the SOFC-GT. The CCHP system, whose main fuel is methane, can generate electricity, cooling effect and heat effect simultaneously. The overall system performance has been evaluated by mathematical models and thermodynamic laws. A parametric analysis is also conducted to examine the effects of some key thermodynamic parameters on the system performance. Results indicate that the overall energy conversion efficiency exceeds 80% under the given conditions, and it is also found that the increasing the fuel flow rate can improve overall energy conversion efficiency, even though both the SOFC efficiency and electricity efficiency decrease. Moreover, with an increased compressor pressure ratio, the SOFC efficiency, electricity efficiency and overall energy conversion efficiency all increase. Ammonia concentration and pressure entering ammonia-water turbine can also affect the CCHP system performance.

  9. Cell-free protein expression based on extracts from CHO cells.

    Science.gov (United States)

    Brödel, Andreas K; Sonnabend, Andrei; Kubick, Stefan

    2014-01-01

    Protein expression systems are widely used in biotechnology and medicine for the efficient and economic production of therapeutic proteins. Today, cultivated Chinese hamster ovary (CHO) cells are the market dominating mammalian cell-line for the production of complex therapeutic proteins. Despite this outstanding potential of CHO cells, no high-yield cell-free system based on translationally active lysates from these cells has been reported so far. To date, CHO cell extracts have only been used as a foundational research tool for understanding mRNA translation (Lodish et al., 1974; McDowell et al., 1972). In the present study, we address this fact by establishing a novel cell-free protein expression system based on extracts from cultured CHO cells. Lysate preparation, adaptation of in vitro reaction conditions and the construction of particular expression vectors are considered for high-yield protein production. A specific in vitro expression vector, which includes an internal ribosome entry site (IRES) from the intergenic region (IGR) of the Cricket paralysis virus (CrPV), has been constructed in order to obtain optimal performance. The IGR IRES is supposed to bind directly to the eukaryotic 40S ribosomal subunit thereby bypassing the process of translation initiation, which is often a major bottleneck in cell-free systems. The combination of expression vector and optimized CHO cell extracts enables the production of approximately 50 µg/mL active firefly luciferase within 4 h. The batch-type cell-free coupled transcription-translation system has the potential to perform post-translational modifications, as shown by the glycosylation of erythropoietin. Accordingly, the system contains translocationally active endogenous microsomes, enabling the co-translational incorporation of membrane proteins into biological membranes. Hence, the presented in vitro translation system is a powerful tool for the fast and convenient optimization of expression constructs, the

  10. Fingerprint Indoor Position System Based

    OpenAIRE

    José Antonio Gómez Martin; Ana Verónica Medina Rodríguez; Enrique Dorronzoro Zubiete; Octavio Rivera Romero; Sergio Martín Guillén

    2013-01-01

    This paper presents a research and a development of a fingerprint-indoor-positioning system using the Received Signal Strength Indication (RSSI) of a Wireless Sensor Network (WSN). The WSN implementation is based on two different protocol stacks: BitCloud and OpenMAC, a certified ZigBee Compliant Platform (ZCP) and an IEEE 802.15.4 embedded software implementation respectively, both from Atmel, and the system uses two different fingerprint algorithms, Simple and Centroid. A comparative analys...

  11. A hybrid base isolation system

    Energy Technology Data Exchange (ETDEWEB)

    Hart, G.C. [Univ. of California, Los Angeles, CA (United States); Lobo, R.F.; Srinivasan, M. [Hart Consultant Group, Santa Monica, CA (United States); Asher, J.W. [kpff Engineers, Santa Monica, CA (United States)

    1995-12-01

    This paper proposes a new analysis procedure for hybrid base isolation buildings when considering the displacement response of a base isolated building to wind loads. The system is considered hybrid because of the presence of viscous dampers in the building above the isolator level. The proposed analysis approach incorporates a detailed site specific wind study combined with a dynamic nonlinear analysis of the building response.

  12. Immobilization of Lactobacillus rhamnosus in mesoporous silica-based material: An efficiency continuous cell-recycle fermentation system for lactic acid production.

    Science.gov (United States)

    Zhao, Zijian; Xie, Xiaona; Wang, Zhi; Tao, Yanchun; Niu, Xuedun; Huang, Xuri; Liu, Li; Li, Zhengqiang

    2016-06-01

    Lactic acid bacteria immobilization methods have been widely used for lactic acid production. Until now, the most common immobilization matrix used is calcium alginate. However, Ca-alginate gel disintegrated during lactic acid fermentation. To overcome this deficiency, we developed an immobilization method in which Lactobacillus rhamnosus cells were successfully encapsulated into an ordered mesoporous silica-based material under mild conditions with a high immobilization efficiency of 78.77% by using elemental analysis. We also optimized the cultivation conditions of the immobilized L. rhamnosus and obtained a high glucose conversion yield of 92.4%. Furthermore, L. rhamnosus encapsulated in mesoporous silica-based material exhibited operational stability during repeated fermentation processes and no decrease in lactic acid production up to 8 repeated batches.

  13. Immobilization of Lactobacillus rhamnosus in mesoporous silica-based material: An efficiency continuous cell-recycle fermentation system for lactic acid production.

    Science.gov (United States)

    Zhao, Zijian; Xie, Xiaona; Wang, Zhi; Tao, Yanchun; Niu, Xuedun; Huang, Xuri; Liu, Li; Li, Zhengqiang

    2016-06-01

    Lactic acid bacteria immobilization methods have been widely used for lactic acid production. Until now, the most common immobilization matrix used is calcium alginate. However, Ca-alginate gel disintegrated during lactic acid fermentation. To overcome this deficiency, we developed an immobilization method in which Lactobacillus rhamnosus cells were successfully encapsulated into an ordered mesoporous silica-based material under mild conditions with a high immobilization efficiency of 78.77% by using elemental analysis. We also optimized the cultivation conditions of the immobilized L. rhamnosus and obtained a high glucose conversion yield of 92.4%. Furthermore, L. rhamnosus encapsulated in mesoporous silica-based material exhibited operational stability during repeated fermentation processes and no decrease in lactic acid production up to 8 repeated batches. PMID:26803707

  14. Avicequinone C isolated from Avicennia marina exhibits 5α-reductase-type 1 inhibitory activity using an androgenic alopecia relevant cell-based assay system.

    Science.gov (United States)

    Jain, Ruchy; Monthakantirat, Orawan; Tengamnuay, Parkpoom; De-Eknamkul, Wanchai

    2014-01-01

    Avicennia marina (AM) exhibits various biological activities and has been traditionally used in Egypt to cure skin diseases. In this study, the methanolic heartwood extract of AM was evaluated for inhibitory activity against 5α-reductase (5α-R) [E.C.1.3.99.5], the enzyme responsible for the over-production of 5α-dihydrotestosterone (5α-DHT) causing androgenic alopecia (AGA). An AGA-relevant cell-based assay was developed using human hair dermal papilla cells (HHDPCs), the main regulator of hair growth and the only cells within the hair follicle that are the direct site of 5α-DHT action, combined with a non-radioactive thin layer chromatography (TLC) detection technique. The results revealed that AM is a potent 5α-R type 1 (5α-R1) inhibitor, reducing the 5α-DHT production by 52% at the final concentration of 10 µg/mL. Activity-guided fractionation has led to the identification of avicequinone C, a furanonaphthaquinone, as a 5α-R1 inhibitor with an IC50 of 9.94 ± 0.33 µg/mL or 38.8 ± 1.29 µM. This paper is the first to report anti-androgenic activity through 5α-R1 inhibition of AM and avicequinone C. PMID:24858268

  15. Avicequinone C Isolated from Avicennia marina Exhibits 5α-Reductase-Type 1 Inhibitory Activity Using an Androgenic Alopecia Relevant Cell-Based Assay System

    Directory of Open Access Journals (Sweden)

    Ruchy Jain

    2014-05-01

    Full Text Available Avicennia marina (AM exhibits various biological activities and has been traditionally used in Egypt to cure skin diseases. In this study, the methanolic heartwood extract of AM was evaluated for inhibitory activity against 5α-reductase (5α-R [E.C.1.3.99.5], the enzyme responsible for the over-production of 5α-dihydrotestosterone (5α-DHT causing androgenic alopecia (AGA. An AGA-relevant cell-based assay was developed using human hair dermal papilla cells (HHDPCs, the main regulator of hair growth and the only cells within the hair follicle that are the direct site of 5α-DHT action, combined with a non-radioactive thin layer chromatography (TLC detection technique. The results revealed that AM is a potent 5α-R type 1 (5α-R1 inhibitor, reducing the 5α-DHT production by 52% at the final concentration of 10 µg/mL. Activity-guided fractionation has led to the identification of avicequinone C, a furanonaphthaquinone, as a 5α-R1 inhibitor with an IC50 of 9.94 ± 0.33 µg/mL or 38.8 ± 1.29 µM. This paper is the first to report anti-androgenic activity through 5α-R1 inhibition of AM and avicequinone C.

  16. Protective T Cell and Antibody Immune Responses against Hepatitis C Virus Achieved Using a Biopolyester-Bead-Based Vaccine Delivery System.

    Science.gov (United States)

    Martínez-Donato, G; Piniella, B; Aguilar, D; Olivera, S; Pérez, A; Castañedo, Y; Alvarez-Lajonchere, L; Dueñas-Carrera, S; Lee, J W; Burr, N; Gonzalez-Miro, M; Rehm, B H A

    2016-04-01

    Hepatitis C virus (HCV) infection is a major worldwide problem. Chronic hepatitis C is recognized as one of the major causes of cirrhosis, hepatocellular carcinoma, and liver failure. Although new, directly acting antiviral therapies are suggested to overcome the low efficacy and adverse effects observed for the current standard of treatment, an effective vaccine would be the only way to certainly eradicate HCV infection. Recently, polyhydroxybutyrate beads produced by engineeredEscherichia colishowed efficacy as a vaccine delivery system. Here, an endotoxin-freeE. colistrain (ClearColi) was engineered to produce polyhydroxybutyrate beads displaying the core antigen on their surface (Beads-Core) and their immunogenicity was evaluated in BALB/c mice. Immunization with Beads-Core induced gamma interferon (IFN-γ) secretion and a functional T cell immune response against the HCV Core protein. With the aim to target broad T and B cell determinants described for HCV, Beads-Core mixed with HCV E1, E2, and NS3 recombinant proteins was also evaluated in BALB/c mice. Remarkably, only three immunization with Beads-Core+CoE1E2NS3/Alum (a mixture of 0.1 μg Co.120, 16.7 μg E1.340, 16.7 μg E2.680, and 10 μg NS3 adjuvanted in aluminum hydroxide [Alum]) induced a potent antibody response against E1 and E2 and a broad IFN-γ secretion and T cell response against Core and all coadministered antigens. This immunological response mediated protective immunity to viremia as assessed in a viral surrogate challenge model. Overall, it was shown that engineered biopolyester beads displaying foreign antigens are immunogenic and might present a particulate delivery system suitable for vaccination against HCV. PMID:26888185

  17. PDMS/glass microfluidic cell culture system for cytotoxicity tests and cells passage

    DEFF Research Database (Denmark)

    Ziolkowska, K.; Jedrych, E.; Kwapiszewski, R.;

    2010-01-01

    In this paper, hybrid (PDMS/glass) microfluidic cell culture system (MCCS) integrated with the concentration gradient generator (CGG) is presented. PDMS gas permeability enabled cells' respiration in the fabricated microdevices and excellent glass hydrophilicity allowed successful cells' seeding....... The human lung carcinoma cells (A549) were cultured in the microdevice for several days. The growth and proliferation of cells was monitored using an inverted fluorescence microscope. After the cells' confluence was achieved in the microchambers, the novel method of cells' passaging in the designed...... microdevice was developed and successfully tested. The MCCS microdevice is fully reusable, i.e. it can be used several times for various cell culture and cytotoxic experiments. The suitability of designed MCCS for cell-based cytotoxicity assay application was verified using 1,4-dioxane as a model toxic agent...

  18. Stem cells in the nervous system.

    Science.gov (United States)

    Maldonado-Soto, Angel R; Oakley, Derek H; Wichterle, Hynek; Stein, Joel; Doetsch, Fiona K; Henderson, Christopher E

    2014-11-01

    Given their capacity to regenerate cells lost through injury or disease, stem cells offer new vistas into possible treatments for degenerative diseases and their underlying causes. As such, stem cell biology is emerging as a driving force behind many studies in regenerative medicine. This review focuses on the current understanding of the applications of stem cells in treating ailments of the human brain, with an emphasis on neurodegenerative diseases. Two types of neural stem cells are discussed: endogenous neural stem cells residing within the adult brain and pluripotent stem cells capable of forming neural cells in culture. Endogenous neural stem cells give rise to neurons throughout life, but they are restricted to specialized regions in the brain. Elucidating the molecular mechanisms regulating these cells is key in determining their therapeutic potential as well as finding mechanisms to activate dormant stem cells outside these specialized microdomains. In parallel, patient-derived stem cells can be used to generate neural cells in culture, providing new tools for disease modeling, drug testing, and cell-based therapies. Turning these technologies into viable treatments will require the integration of basic science with clinical skills in rehabilitation.

  19. Water reactive hydrogen fuel cell power system

    Science.gov (United States)

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-01-21

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  20. Cell-based strategies for vascular regeneration.

    Science.gov (United States)

    Zou, Tongqiang; Fan, Jiabing; Fartash, Armita; Liu, Haifeng; Fan, Yubo

    2016-05-01

    Vascular regeneration is known to play an essential role in the repair of injured tissues mainly through accelerating the repair of vascular injury caused by vascular diseases, as well as the recovery of ischemic tissues. However, the clinical vascular regeneration is still challenging. Cell-based therapy is thought to be a promising strategy for vascular regeneration, since various cells have been identified to exert important influences on the process of vascular regeneration such as the enhanced endothelium formation on the surface of vascular grafts, and the induction of vessel-like network formation in the ischemic tissues. Here are a vast number of diverse cell-based strategies that have been extensively studied in vascular regeneration. These strategies can be further classified into three main categories, including cell transplantation, construction of tissue-engineered grafts, and surface modification of scaffolds. Cells used in these strategies mainly refer to terminally differentiated vascular cells, pluripotent stem cells, multipotent stem cells, and unipotent stem cells. The aim of this review is to summarize the reported research advances on the application of various cells for vascular regeneration, yielding insights into future clinical treatment for injured tissue/organ. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1297-1314, 2016. PMID:26864677

  1. MTJ based MRAM System Design

    Science.gov (United States)

    Tehrani, Saied

    2001-03-01

    Magnetoresistive Random Access Memory (MRAM) is based on magnetic memory elements integrated with CMOS. Key attributes of MRAM technology are nonvolatility and unlimited read and write endurance. MRAM has the potential for high speed, low operating voltage, and high density solid state memory. Our bit architecture is based on a minimum sized active transistor as the isolation device in conjunction with a magnetic tunnel junction element (MTJ) to define the MRAM bit. Our MTJ material stack is composed of two magnetic layers separated by a thin dielectric barrier and a mechanism to pin the polarization of one of the magnetic layers in a fixed direction. The resistance of the memory bit is either low or high dependent on the relative polarization, parallel or anti-parallel, of the free layer with respect to the pinned layer. In this talk we will summarize our progress on Magnetoresistive Random Access Memory (MRAM) based on Magnetic Tunnel Junctions (MTJ). We have demonstrated MTJ material in the 1-1000 kohms-um2 range with MR values above 40mainly governed by the magnetic shape anisotropy that arises from the element boundaries. The switching repeatability, as well as hard axis selectability, are shown to be dependent on both shape and aspect ratio. The MRAM module is inserted in the back-end-of-line (BEOL) interconnect using four additional lithography steps. The source and isolation are shared between neighboring cells to minimize cell area. In this particular architecture, the cell size is 7.2um2, corresponding to 9f2, where f is one-half the metal pitch. Results of 256kb MRAM memory based on integration of MTJ and CMOS will be discussed. The memory cell is a 1T1MTJ, which consists of one transistor and one Magnetic Tunnel Junction, and the organization of the memory is 16kx16. Nonvolatile data storage and read cycle times of less than 50ns have been demonstrated. Read power consumption at 3.0V and 20MHz is about 24mW.This performance is very encouraging for a 0

  2. Production Process for Stem Cell Based Therapeutic Implants: Expansion of the Production Cell Line and Cultivation of Encapsulated Cells

    Science.gov (United States)

    Weber, C.; Pohl, S.; Poertner, R.; Pino-Grace, Pablo; Freimark, D.; Wallrapp, C.; Geigle, P.; Czermak, P.

    Cell based therapy promises the treatment of many diseases like diabetes mellitus, Parkinson disease or stroke. Microencapsulation of the cells protects them against host-vs-graft reactions and thus enables the usage of allogenic cell lines for the manufacturing of cell therapeutic implants. The production process of such implants consists mainly of the three steps expansion of the cells, encapsulation of the cells, and cultivation of the encapsulated cells in order to increase their vitality and thus quality. This chapter deals with the development of fixed-bed bioreactor-based cultivation procedures used in the first and third step of production. The bioreactor system for the expansion of the stem cell line (hMSC-TERT) is based on non-porous glass spheres, which support cell growth and harvesting with high yield and vitality. The cultivation process for the spherical cell based implants leads to an increase of vitality and additionally enables the application of a medium-based differentiation protocol.

  3. Optimization of Buffalo (Bubalus bubalis Embryonic Stem Cell Culture System

    Directory of Open Access Journals (Sweden)

    Mohammad Zandi

    2015-07-01

    Full Text Available Objective: In order to retain an undifferentiated pluripotent state, embryonic stem (ES cells have to be cultured on feeder cell layers. However, use of feeder layers limits stem cell research, since experimental data may result from a combined ES cell and feeder cell response to various stimuli. Materials and Methods: In this experimental study, a buffalo ES cell line was established from in vitro derived blastocysts and characterized by the Alkaline phosphatase (AP and immunoflourescence staining of various pluripotency markers. We examined the effect of various factors like fibroblast growth factor 2 (FGF-2, leukemia inhibitory factor (LIF and Y-27632 to support the growth and maintenance of bubaline ES cells on gelatin coated dishes, in order to establish feeder free culture systems. We also analyzed the effect of feeder-conditioned media on stem cell growth in gelatin based cultures both in the presence as well as in the absence of the growth factors. Results: The results showed that Y-27632, in the presence of FGF-2 and LIF, resulted in higher colony growth and increased expression of Nanog gene. Feeder-Conditioned Medium resulted in a significant increase in growth of buffalo ES cells on gelatin coated plates, however, feeder layer based cultures produced better results than gelatin based cultures. Feeder layers from buffalo fetal fibroblast cells can support buffalo ES cells for more than two years. Conclusion: We developed a feeder free culture system that can maintain buffalo ES cells in the short term, as well as feeder layer based culture that can support the long term maintenance of buffalo ES cells.

  4. Dissolution system reliability data base

    International Nuclear Information System (INIS)

    Computerized, interactive data bases are becoming increasingly important in plant operations. Reliability-centered Maintenance techniques utilize the operational history of components to identify areas where maintenance resources should be focused. The recent US Nuclear Regulatory Commission maintenance ruling requires the identification of problematic components, systems and functions, fault trending, and other related activities. There is a constant demand for the determination of root causes of failures and the documentation and tracking of the resulting corrective actions. Plant operators seek advanced methods to assist in diagnosing process upsets, planning maintenance activities, and documenting equipment warranty information. This paper describes a personal computer (PC)-based reliability data base for a nuclear fuel dissolution system as a tool for addressing these needs

  5. Photoelectrochemical based direct conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Kocha, S.; Arent, D.; Peterson, M. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1995-09-01

    The goal of this research is to develop a stable, cost effective, photoelectrochemical based system that will split water upon illumination, producing hydrogen and oxygen directly, using sunlight as the only energy input. This type of direct conversion system combines a photovoltaic material and an electrolyzer into a single monolithic device. We report on our studies of two multifunction multiphoton photoelectrochemical devices, one based on the ternary semiconductor gallium indium phosphide, (GaInP{sub 2}), and the other one based on amorphous silicon carbide. We also report on our studies of the solid state surface treatment of GaInP{sub 2} as well as our continuing effort to develop synthetic techniques for the attachment of transition metal complexes to the surface of semiconductor electrodes. All our surface studies are directed at controlling the interface energetics and forming stable catalytic surfaces.

  6. Microchip-based immunomagnetic detection of circulating tumor cells.

    Science.gov (United States)

    Hoshino, Kazunori; Huang, Yu-Yen; Lane, Nancy; Huebschman, Michael; Uhr, Jonathan W; Frenkel, Eugene P; Zhang, Xiaojing

    2011-10-21

    Screening for circulating tumor cells (CTCs) in blood has been an object of interest for evidence of progressive disease, status of disease activity, recognition of clonal evolution of molecular changes and for possible early diagnosis of cancer. We describe a new method of microchip-based immunomagnetic CTC detection, in which the benefits of both immunomagnetic assay and the microfluidic device are combined. As the blood sample flows through the microchannel closely above arrayed magnets, cancer cells labeled with magnetic nanoparticles are separated from blood flow and deposited at the bottom wall of the glass coverslip, which allows direct observation of captured cells with a fluorescence microscope. A polydimethylsiloxane (PDMS)-based microchannel fixed on a glass coverslip was used to screen blood samples. The thin, flat dimensions of the microchannel, combined with the sharp magnetic field gradient in the vicinity of arrayed magnets with alternate polarities, lead to an effective capture of labeled cells. Compared to the commercially available CellSearch™ system, fewer (25%) magnetic particles are required to achieve a comparable capture rate, while the screening speed (at an optimal blood flow rate of 10 mL h(-1)) is more than five times faster than those reported previously with a microchannel-based assay. For the screening experiment, blood drawn from healthy subjects into CellSave™ tubes was spiked with cultured cancer cell lines of COLO205 and SKBR3. The blood was then kept at room temperature for 48 hours before the screening, emulating the actual clinical cases of blood screening. Customized Fe(3)O(4) magnetic nanoparticles (Veridex Ferrofluid™) conjugated to anti-epithelial cell adhesion molecule (EpCAM) antibodies were introduced into the blood samples to label cancer cells, and the blood was then run through the microchip device to capture the labelled cells. After capture, the cells were stained with fluorescent labelled anti

  7. An Automatic Indirect Immunofluorescence Cell Segmentation System

    Directory of Open Access Journals (Sweden)

    Yung-Kuan Chan

    2014-01-01

    Full Text Available Indirect immunofluorescence (IIF with HEp-2 cells has been used for the detection of antinuclear autoantibodies (ANA in systemic autoimmune diseases. The ANA testing allows us to scan a broad range of autoantibody entities and to describe them by distinct fluorescence patterns. Automatic inspection for fluorescence patterns in an IIF image can assist physicians, without relevant experience, in making correct diagnosis. How to segment the cells from an IIF image is essential in developing an automatic inspection system for ANA testing. This paper focuses on the cell detection and segmentation; an efficient method is proposed for automatically detecting the cells with fluorescence pattern in an IIF image. Cell culture is a process in which cells grow under control. Cell counting technology plays an important role in measuring the cell density in a culture tank. Moreover, assessing medium suitability, determining population doubling times, and monitoring cell growth in cultures all require a means of quantifying cell population. The proposed method also can be used to count the cells from an image taken under a fluorescence microscope.

  8. Systems Biology for Organotypic Cell Cultures

    Energy Technology Data Exchange (ETDEWEB)

    Grego, Sonia [RTI International, Research Triangle Park, NC (United States); Dougherty, Edward R. [Texas A & M Univ., College Station, TX (United States); Alexander, Francis J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Auerbach, Scott S. [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States); Berridge, Brian R. [GlaxoSmithKline, Research Triangle Park, NC (United States); Bittner, Michael L. [Translational Genomics Research Inst., Phoenix, AZ (United States); Casey, Warren [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States); Cooley, Philip C. [RTI International, Research Triangle Park, NC (United States); Dash, Ajit [HemoShear Therapeutics, Charlottesville, VA (United States); Ferguson, Stephen S. [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States); Fennell, Timothy R. [RTI International, Research Triangle Park, NC (United States); Hawkins, Brian T. [RTI International, Research Triangle Park, NC (United States); Hickey, Anthony J. [RTI International, Research Triangle Park, NC (United States); Kleensang, Andre [Johns Hopkins Univ., Baltimore, MD (United States). Center for Alternatives to Animal Testing; Liebman, Michael N. [IPQ Analytics, Kennett Square, PA (United States); Martin, Florian [Phillip Morris International, Neuchatel (Switzerland); Maull, Elizabeth A. [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States); Paragas, Jason [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Qiao, Guilin [Defense Threat Reduction Agency, Ft. Belvoir, VA (United States); Ramaiahgari, Sreenivasa [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States); Sumner, Susan J. [RTI International, Research Triangle Park, NC (United States); Yoon, Miyoung [The Hamner Inst. for Health Sciences, Research Triangle Park, NC (United States); ScitoVation, Research Triangle Park, NC (United States)

    2016-08-04

    Translating in vitro biological data into actionable information related to human health holds the potential to improve disease treatment and risk assessment of chemical exposures. While genomics has identified regulatory pathways at the cellular level, translation to the organism level requires a multiscale approach accounting for intra-cellular regulation, inter-cellular interaction, and tissue/organ-level effects. Tissue-level effects can now be probed in vitro thanks to recently developed systems of three-dimensional (3D), multicellular, “organotypic” cell cultures, which mimic functional responses of living tissue. However, there remains a knowledge gap regarding interactions across different biological scales, complicating accurate prediction of health outcomes from molecular/genomic data and tissue responses. Systems biology aims at mathematical modeling of complex, non-linear biological systems. We propose to apply a systems biology approach to achieve a computational representation of tissue-level physiological responses by integrating empirical data derived from organotypic culture systems with computational models of intracellular pathways to better predict human responses. Successful implementation of this integrated approach will provide a powerful tool for faster, more accurate and cost-effective screening of potential toxicants and therapeutics. On September 11, 2015, an interdisciplinary group of scientists, engineers, and clinicians gathered for a workshop in Research Triangle Park, North Carolina, to discuss this ambitious goal. Participants represented laboratory-based and computational modeling approaches to pharmacology and toxicology, as well as the pharmaceutical industry, government, non-profits, and academia. Discussions focused on identifying critical system perturbations to model, the computational tools required, and the experimental approaches best suited to generating key data. This consensus report summarizes the discussions held.

  9. Seca Coal-Based Systems Program

    International Nuclear Information System (INIS)

    This report summarizes the progress made during the August 1, 2006 - May 31, 2008 award period under Cooperative Agreement DE-FC26-05NT42614 for the U. S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled 'SECA Coal Based Systems'. The initial overall objective of this program was to design, develop, and demonstrate multi-MW integrated gasification fuel cell (IGFC) power plants with >50% overall efficiency from coal (HHV) to AC power. The focus of the program was to develop low-cost, high performance, modular solid oxide fuel cell (SOFC) technology to support coal gas IGFC power systems. After a detailed GE internal review of the SOFC technology, the program was de-scoped at GE's request. The primary objective of this program was then focused on developing a performance degradation mitigation path for high performing, cost-effective solid oxide fuel cells (SOFCs). There were two initial major objectives in this program. These were: (1) Develop and optimize a design of a >100 MWe integrated gasification fuel cell (IGFC) power plant; (2) Resolve identified barrier issues concerning the long-term economic performance of SOFC. The program focused on designing and cost estimating the IGFC system and resolving technical and economic barrier issues relating to SOFC. In doing so, manufacturing options for SOFC cells were evaluated, options for constructing stacks based upon various cell configurations identified, and key performance characteristics were identified. Key factors affecting SOFC performance degradation for cells in contact with metallic interconnects were be studied and a fundamental understanding of associated mechanisms was developed using a fixed materials set. Experiments and modeling were carried out to identify key processes/steps affecting cell performance degradation under SOFC operating conditions. Interfacial microstructural and elemental changes were characterized, and their relationships to observed degradation

  10. Seca Coal-Based Systems Program

    Energy Technology Data Exchange (ETDEWEB)

    Matthew Alinger

    2008-05-31

    This report summarizes the progress made during the August 1, 2006 - May 31, 2008 award period under Cooperative Agreement DE-FC26-05NT42614 for the U. S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled 'SECA Coal Based Systems'. The initial overall objective of this program was to design, develop, and demonstrate multi-MW integrated gasification fuel cell (IGFC) power plants with >50% overall efficiency from coal (HHV) to AC power. The focus of the program was to develop low-cost, high performance, modular solid oxide fuel cell (SOFC) technology to support coal gas IGFC power systems. After a detailed GE internal review of the SOFC technology, the program was de-scoped at GE's request. The primary objective of this program was then focused on developing a performance degradation mitigation path for high performing, cost-effective solid oxide fuel cells (SOFCs). There were two initial major objectives in this program. These were: (1) Develop and optimize a design of a >100 MWe integrated gasification fuel cell (IGFC) power plant; (2) Resolve identified barrier issues concerning the long-term economic performance of SOFC. The program focused on designing and cost estimating the IGFC system and resolving technical and economic barrier issues relating to SOFC. In doing so, manufacturing options for SOFC cells were evaluated, options for constructing stacks based upon various cell configurations identified, and key performance characteristics were identified. Key factors affecting SOFC performance degradation for cells in contact with metallic interconnects were be studied and a fundamental understanding of associated mechanisms was developed using a fixed materials set. Experiments and modeling were carried out to identify key processes/steps affecting cell performance degradation under SOFC operating conditions. Interfacial microstructural and elemental changes were characterized, and their relationships to observed

  11. Evaluation of clinical trial eligibility and prognostic indices in a population-based cohort of systemic peripheral T-cell lymphomas from the Danish Lymphoma Registry

    DEFF Research Database (Denmark)

    Pedersen, Martin Bjerregaard; Hamilton-Dutoit, Stephen Jacques; Bendix, Knud;

    2015-01-01

    . The aim of the present study was to evaluate CT eligibility and selected prognostic indices in a population-based PTCL cohort of 481 PTCL patients identified from the Danish Lymphoma Registry in the period 2000-2010. According to five predefined parameters (age, performance status, P-creatinine, P....... Overall, 41% of the patients were considered eligible for interventional CTs implicating curatively intended multiagent chemotherapy, including, if considered appropriate, consolidating stem cell transplantation (SCT), as part of the upfront management strategy. Moreover, 28% was elderly fit and eligible...... for interventional CT, including those with SCT as part of the trial design. Approximately 7% were defined as 'too frail' for aggressive treatment schedules, whereas 24% were deemed not to be eligible for any CT. Both overall and progression-free survivals were effectively predicted by IPI and PIT (p

  12. Fingerprint Indoor Position System Based

    Directory of Open Access Journals (Sweden)

    José Antonio Gómez Martin

    2013-01-01

    Full Text Available This paper presents a research and a development of a fingerprint-indoor-positioning system using the Received Signal Strength Indication (RSSI of a Wireless Sensor Network (WSN. The WSN implementation is based on two different protocol stacks: BitCloud and OpenMAC, a certified ZigBee Compliant Platform (ZCP and an IEEE 802.15.4 embedded software implementation respectively, both from Atmel, and the system uses two different fingerprint algorithms, Simple and Centroid. A comparative analysis of both algorithms using both protocol stacks implementations have been performed to ascertain the best WSN protocol stack and the best algorithm for positioning purposes.

  13. Integrating fuel cell power systems into building physical plants

    Energy Technology Data Exchange (ETDEWEB)

    Carson, J. [KCI Technologies, Inc., Hunt Valley, MD (United States)

    1996-12-31

    This paper discusses the integration of fuel cell power plants and absorption chillers to cogenerate chilled water or hot water/steam for all weather air conditioning as one possible approach to building system applications. Absorption chillers utilize thermal energy in an absorption based cycle to chill water. It is feasible to use waste heat from fuel cells to provide hydronic heating and cooling. Performance regimes will vary as a function of the supply and quality of waste heat. Respective performance characteristics of fuel cells, absorption chillers and air conditioning systems will define relationships between thermal and electrical load capacities for the combined systems. Specifically, this paper develops thermodynamic relationships between bulk electrical power and cooling/heating capacities for combined fuel cell and absorption chiller system in building applications.

  14. Monolithic fuel cell based power source for burst power generation

    Science.gov (United States)

    Fee, D. C.; Blackburn, P. E.; Busch, D. E.; Dees, D. W.; Dusek, J.; Easler, T. E.; Ellingson, W. A.; Flandermeyer, B. K.; Fousek, R. J.; Heiberger, J. J.

    A unique fuel cell coupled with a low power nuclear reactor presents an attractive approach for SDI burst power requirements. The monolithic fuel cell looks attractive for space applications and represents a quantum jump in fuel cell technology. Such a breakthrough in design is the enabling technology for lightweight, low volume power sources for space based pulse power systems. The monolith is unique among fuel cells in being an all solid state device. The capability for miniaturization, inherent in solid state devices, gives the low volume required for space missions. In addition, the solid oxide fuel cell technology employed in the monolith has high temperature reject heat and can be operated in either closed or open cycles. Both these features are attractive for integration into a burst power system.

  15. Nucleic acid based logical systems.

    Science.gov (United States)

    Han, Da; Kang, Huaizhi; Zhang, Tao; Wu, Cuichen; Zhou, Cuisong; You, Mingxu; Chen, Zhuo; Zhang, Xiaobing; Tan, Weihong

    2014-05-12

    Researchers increasingly visualize a significant role for artificial biochemical logical systems in biological engineering, much like digital logic circuits in electrical engineering. Those logical systems could be utilized as a type of servomechanism to control nanodevices in vitro, monitor chemical reactions in situ, or regulate gene expression in vivo. Nucleic acids (NA), as carriers of genetic information with well-regulated and predictable structures, are promising materials for the design and engineering of biochemical circuits. A number of logical devices based on nucleic acids (NA) have been designed to handle various processes for technological or biotechnological purposes. This article focuses on the most recent and important developments in NA-based logical devices and their evolution from in vitro, through cellular, even towards in vivo biological applications.

  16. Spectrin-based skeleton as an actor in cell signaling

    OpenAIRE

    Machnicka, B.; Grochowalska, R.; Bogusławska, D. M.; Sikorski, A F; Lecomte, M C

    2011-01-01

    This review focuses on the recent advances in functions of spectrins in non-erythroid cells. We discuss new data concerning the commonly known role of the spectrin-based skeleton in control of membrane organization, stability and shape, and tethering protein mosaics to the cellular motors and to all major filament systems. Particular effort has been undertaken to highlight recent advances linking spectrin to cell signaling phenomena and its participation in signal transduction pathways in man...

  17. Clickable Poly(ethylene glycol)-Microsphere-Based Cell Scaffolds

    OpenAIRE

    Nguyen, Peter K.; Snyder, Christopher G.; Shields, Jason D.; Smith, Amanda W.; Elbert, Donald L.

    2013-01-01

    Clickable poly(ethylene glycol) (PEG) derivatives are used with two sequential aqueous two-phase systems to produce microsphere-based scaffolds for cell encapsulation. In the first step, sodium sulfate causes phase separation of the clickable PEG precursors and is followed by rapid geleation to form microspheres in the absence of organic solvent or surfactant. The microspheres are washed and then deswollen in dextran solutions in the presence of cells, producing tightly packed scaffolds that ...

  18. Microfluidic-Based Robotic Sampling System for Radioactive Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Jack D. Law; Julia L. Tripp; Tara E. Smith; Veronica J. Rutledge; Troy G. Garn; John Svoboda; Larry Macaluso

    2014-02-01

    A novel microfluidic based robotic sampling system has been developed for sampling and analysis of liquid solutions in nuclear processes. This system couples the use of a microfluidic sample chip with a robotic system designed to allow remote, automated sampling of process solutions in-cell and facilitates direct coupling of the microfluidic sample chip with analytical instrumentation. This system provides the capability for near real time analysis, reduces analytical waste, and minimizes the potential for personnel exposure associated with traditional sampling methods. A prototype sampling system was designed, built and tested. System testing demonstrated operability of the microfluidic based sample system and identified system modifications to optimize performance.

  19. A Cell-in-the-Loop Approach to Systems Modelling and Simulation of Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    James Marco

    2015-08-01

    Full Text Available This research is aligned with the engineering challenge of scaling-up individual battery cells into a complete energy storage system (ESS. Manufacturing tolerances, coupled with thermal gradients and the differential electrical loading of adjacent cells, can result in significant variations in the rate of cell degradation, energy distribution and ESS performance. The uncertain transition from cell to system often manifests itself in over-engineered, non-optimal ESS designs within both the transport and energy sectors. To alleviate these issues, the authors propose a novel model-based framework for cell-in-the-loop simulation (CILS in which a physical cell may be integrated within a complete model of an ESS and exercised against realistic electrical and thermal loads in real-time. This paper focuses on the electrical integration of both real and simulated cells within the CILS test environment. Validation of the CILS approach using real-world electric vehicle data is presented for an 18650 cell. The cell is integrated within a real-time simulation model of a series string of similar cells in a 4sp1 configuration. Results are presented that highlight the impact of cell variability (i.e., capacity and impedance on the energy available from the multi-cell system and the useable capacity of the physical cell.

  20. Stem Cell-Based Cell Carrier for Targeted Oncolytic Virotherapy: Translational Opportunity and Open Questions.

    Science.gov (United States)

    Kim, Janice; Hall, Robert R; Lesniak, Maciej S; Ahmed, Atique U

    2015-11-27

    Oncolytic virotherapy for cancer is an innovative therapeutic option where the ability of a virus to promote cell lysis is harnessed and reprogrammed to selectively destroy cancer cells. Such treatment modalities exhibited antitumor activity in preclinical and clinical settings and appear to be well tolerated when tested in clinical trials. However, the clinical success of oncolytic virotherapy has been significantly hampered due to the inability to target systematic metastasis. This is partly due to the inability of the therapeutic virus to survive in the patient circulation, in order to target tumors at distant sites. An early study from various laboratories demonstrated that cells infected with oncolytic virus can protect the therapeutic payload form the host immune system as well as function as factories for virus production and enhance the therapeutic efficacy of oncolytic virus. While a variety of cell lineages possessed potential as cell carriers, copious investigation has established stem cells as a very attractive cell carrier system in oncolytic virotherapy. The ideal cell carrier desire to be susceptible to viral infection as well as support viral infection, maintain immunosuppressive properties to shield the loaded viruses from the host immune system, and most importantly possess an intrinsic tumor homing ability to deliver loaded viruses directly to the site of the metastasis-all qualities stem cells exhibit. In this review, we summarize the recent work in the development of stem cell-based carrier for oncolytic virotherapy, discuss the advantages and disadvantages of a variety of cell carriers, especially focusing on why stem cells have emerged as the leading candidate, and finally propose a future direction for stem cell-based targeted oncolytic virotherapy that involves its establishment as a viable treatment option for cancer patients in the clinical setting.

  1. Regenerative fuel cell systems R and D

    Energy Technology Data Exchange (ETDEWEB)

    Mitlitsky, F.; Myers, B.; Weisberg, A.H. [Lawrence Livermore National Lab., Livermore, CA (United States)

    1998-08-01

    Regenerative fuel cell (RFC) systems produce power and electrolytically regenerate their reactants using stacks of electrochemical cells. Energy storage systems with extremely high specific energy (> 400 Wh/kg) have been designed that use lightweight pressure vessels to contain the gases generated by reversible (unitized) regenerative fuel cells (URFCs). Progress is reported on the development, integration, and operation of rechargeable energy storage systems with such high specific energy. Lightweight pressure vessels that enable high specific energies have been designed with performance factors (burst pressure/internal volume/tank weight) > 50 km (2.0 million inches), and a vessel with performance factor of 40 km (1.6 million inches) was fabricated. New generations of both advanced and industry-supplied hydrogen tankage are under development. A primary fuel cell test rig with a single cell (46 cm{sup 2} active area) has been modified and operated reversibly as a URFC (for up to 2010 cycles on a single cell). This URFC uses bifunctional electrodes (oxidation and reduction electrodes reverse roles when switching from charge to discharge, as with a rechargeable battery) and cathode feed electrolysis (water is fed from the hydrogen side of the cell). Recent modifications also enable anode feed electrolysis (water is fed from the oxygen side of the cell). Hydrogen/halogen URFCs, capable of higher round-trip efficiency than hydrogen/oxygen URFCs, have been considered, and will be significantly heavier. Progress is reported on higher performance hydrogen/oxygen URFC operation with reduced catalyst loading.

  2. Nanowire-based All Oxide Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang*, Benjamin D. Yuhas and Peidong; Yang, Peidong

    2008-12-07

    We present an all-oxide solar cell fabricated from vertically oriented zinc oxide nanowires and cuprous oxide nanoparticles. Our solar cell consists of vertically oriented n-type zinc oxide nanowires, surrounded by a film constructed from p-type cuprous oxide nanoparticles. Our solution-based synthesis of inexpensive and environmentally benign oxide materials in a solar cell would allow for the facile production of large-scale photovoltaic devices. We found that the solar cell performance is enhanced with the addition of an intermediate oxide insulating layer between the nanowires and the nanoparticles. This observation of the important dependence of the shunt resistance on the photovoltaic performance is widely applicable to any nanowire solar cell constructed with the nanowire array in direct contact with one electrode.

  3. Global behavior of gear system using mixed cell mapping

    Institute of Scientific and Technical Information of China (English)

    SHEN; Yunwen; LIU; Mengjun; DONG; Haijun

    2004-01-01

    In some mechanical nonlinear systems, the transient motion will be undergoing a very long process and the attractor-basin boundaries are so complicated that some difficulties occur in analyzing the system global behavior. To solve this problem a mixed cell mapping method based on the point mapping and the principle of simple cell mapping is developed. The algorithm of the mixed cell mapping is studied. A dynamic model of a gear pair is established with the backlash, damping, transmission error and the time-varying stiffness taken into consideration. The global behaviors of this system are analyzed. The coexistence of the system attractors and the respective attractor-basin of each attractor with different parameters are obtained, thus laying a theoretical basis for improvement of the dynamic behaviors of gear system.

  4. Sensitive-cell-based fish chromatophore biosensor

    Science.gov (United States)

    Plant, Thomas K.; Chaplen, Frank W.; Jovanovic, Goran; Kolodziej, Wojtek; Trempy, Janine E.; Willard, Corwin; Liburdy, James A.; Pence, Deborah V.; Paul, Brian K.

    2004-07-01

    A sensitive biosensor (cytosensor) has been developed based on color changes in the toxin-sensitive colored living cells of fish. These chromatophores are highly sensitive to the presence of many known and unknown toxins produced by microbial pathogens and undergo visible color changes in a dose-dependent manner. The chromatophores are immobilized and maintained in a viable state while potential pathogens multiply and fish cell-microbe interactions are monitored. Low power LED lighting is used to illuminate the chromatophores which are magnified using standard optical lenses and imaged onto a CCD array. Reaction to toxins is detected by observing changes is the total area of color in the cells. These fish chromatophores are quite sensitive to cholera toxin, Staphococcus alpha toxin, and Bordatella pertussis toxin. Numerous other toxic chemical and biological agents besides bacterial toxins also cause readily detectable color effects in chromatophores. The ability of the chromatophore cell-based biosensor to distinguish between different bacterial pathogens was examined. Toxin producing strains of Salmonella enteritis, Vibrio parahaemolyticus, and Bacillus cereus induced movement of pigmented organelles in the chromatophore cells and this movement was measured by changes in the optical density over time. Each bacterial pathogen elicited this measurable response in a distinctive and signature fashion. These results suggest a chromatophore cell-based biosensor assay may be applicable for the detection and identification of virulence activities associated with certain air-, food-, and water-borne bacterial pathogens.

  5. Biotoxin Detection Using Cell-Based Sensors

    Directory of Open Access Journals (Sweden)

    Pratik Banerjee

    2013-11-01

    Full Text Available Cell-based biosensors (CBBs utilize the principles of cell-based assays (CBAs by employing living cells for detection of different analytes from environment, food, clinical, or other sources. For toxin detection, CBBs are emerging as unique alternatives to other analytical methods. The main advantage of using CBBs for probing biotoxins and toxic agents is that CBBs respond to the toxic exposures in the manner related to actual physiologic responses of the vulnerable subjects. The results obtained from CBBs are based on the toxin-cell interactions, and therefore, reveal functional information (such as mode of action, toxic potency, bioavailability, target tissue or organ, etc. about the toxin. CBBs incorporate both prokaryotic (bacteria and eukaryotic (yeast, invertebrate and vertebrate cells. To create CBB devices, living cells are directly integrated onto the biosensor platform. The sensors report the cellular responses upon exposures to toxins and the resulting cellular signals are transduced by secondary transducers generating optical or electrical signals outputs followed by appropriate read-outs. Examples of the layout and operation of cellular biosensors for detection of selected biotoxins are summarized.

  6. Biotoxin detection using cell-based sensors.

    Science.gov (United States)

    Banerjee, Pratik; Kintzios, Spyridon; Prabhakarpandian, Balabhaskar

    2013-12-01

    Cell-based biosensors (CBBs) utilize the principles of cell-based assays (CBAs) by employing living cells for detection of different analytes from environment, food, clinical, or other sources. For toxin detection, CBBs are emerging as unique alternatives to other analytical methods. The main advantage of using CBBs for probing biotoxins and toxic agents is that CBBs respond to the toxic exposures in the manner related to actual physiologic responses of the vulnerable subjects. The results obtained from CBBs are based on the toxin-cell interactions, and therefore, reveal functional information (such as mode of action, toxic potency, bioavailability, target tissue or organ, etc.) about the toxin. CBBs incorporate both prokaryotic (bacteria) and eukaryotic (yeast, invertebrate and vertebrate) cells. To create CBB devices, living cells are directly integrated onto the biosensor platform. The sensors report the cellular responses upon exposures to toxins and the resulting cellular signals are transduced by secondary transducers generating optical or electrical signals outputs followed by appropriate read-outs. Examples of the layout and operation of cellular biosensors for detection of selected biotoxins are summarized. PMID:24335754

  7. Space-Based Lidar Systems

    Science.gov (United States)

    Sun, Xiaoli

    2012-01-01

    An overview of space-based lidar systems is presented. from the first laser altimeter on APOLLO 15 mission in 1971 to the Mercury Laser Altimeter on MESSENGER mission currently in orbit, and those currently under development. Lidar, which stands for Light Detection And Ranging, is a powerful tool in remote sensing from space. Compared to radars, lidars operate at a much shorter wavelength with a much narrower beam and much smaller transmitter and receiver. Compared to passive remote sensing instruments. lidars carry their own light sources and can continue measuring day and night. and over polar regions. There are mainly two types of lidars depending on the types of measurements. lidars that are designed to measure the distance and properties of hard targets are often called laser rangers or laser altimeters. They are used to obtain the surface elevation and global shape of a planet from the laser pulse time-of-night and the spacecraft orbit position. lidars that are designed to measure the backscattering and absorption of a volume scatter, such as clouds and aerosols, are often just called lidars and categorized by their measurements. such as cloud and aerosol lidar, wind lidar, CO2 lidar, and so on. The advantages of space-based lidar systems over ground based lidars are the abilities of global coverage and continuous measurements.

  8. Stem cell-based therapies for HIV/AIDS.

    Science.gov (United States)

    Pernet, Olivier; Yadav, Swati Seth; An, Dong Sung

    2016-08-01

    One of the current focuses in HIV/AIDS research is to develop a novel therapeutic strategy that can provide a life-long remission of HIV/AIDS without daily drug treatment and, ultimately, a cure for HIV/AIDS. Hematopoietic stem cell-based anti-HIV gene therapy aims to reconstitute the patient immune system by transplantation of genetically engineered hematopoietic stem cells with anti-HIV genes. Hematopoietic stem cells can self-renew, proliferate and differentiate into mature immune cells. In theory, anti-HIV gene-modified hematopoietic stem cells can continuously provide HIV-resistant immune cells throughout the life of a patient. Therefore, hematopoietic stem cell-based anti-HIV gene therapy has a great potential to provide a life-long remission of HIV/AIDS by a single treatment. Here, we provide a comprehensive review of the recent progress of developing anti-HIV genes, genetic modification of hematopoietic stem progenitor cells, engraftment and reconstitution of anti-HIV gene-modified immune cells, HIV inhibition in in vitro and in vivo animal models, and in human clinical trials. PMID:27151309

  9. DNA-Based Enzyme Reactors and Systems

    Directory of Open Access Journals (Sweden)

    Veikko Linko

    2016-07-01

    Full Text Available During recent years, the possibility to create custom biocompatible nanoshapes using DNA as a building material has rapidly emerged. Further, these rationally designed DNA structures could be exploited in positioning pivotal molecules, such as enzymes, with nanometer-level precision. This feature could be used in the fabrication of artificial biochemical machinery that is able to mimic the complex reactions found in living cells. Currently, DNA-enzyme hybrids can be used to control (multi-enzyme cascade reactions and to regulate the enzyme functions and the reaction pathways. Moreover, sophisticated DNA structures can be utilized in encapsulating active enzymes and delivering the molecular cargo into cells. In this review, we focus on the latest enzyme systems based on novel DNA nanostructures: enzyme reactors, regulatory devices and carriers that can find uses in various biotechnological and nanomedical applications.

  10. Stem Cell-Based Cell Therapy for Glomerulonephritis

    Directory of Open Access Journals (Sweden)

    Meiling Jin

    2014-01-01

    Full Text Available Glomerulonephritis (GN, characterized by immune-mediated inflammatory changes in the glomerular, is a common cause of end stage renal disease. Therapeutic options for glomerulonephritis applicable to all cases mainly include symptomatic treatment and strategies to delay progression. In the attempt to yield innovative interventions fostering the limited capability of regeneration of renal tissue after injury and the uncontrolled pathological process by current treatments, stem cell-based therapy has emerged as novel therapy for its ability to inhibit inflammation and promote regeneration. Many basic and clinical studies have been performed that support the ability of various stem cell populations to ameliorate glomerular injury and improve renal function. However, there is a long way before putting stem cell-based therapy into clinical practice. In the present article, we aim to review works performed with respect to the use of stem cell of different origins in GN, and to discuss the potential mechanism of therapeutic effect and the challenges for clinical application of stem cells.

  11. IBCIS:Intelligent blood cell identification system

    Institute of Scientific and Technical Information of China (English)

    Adnan Khashman

    2008-01-01

    The analysis of blood cells in microscope images can provide useful information concerning the health of patients.There are three major blood cell types,namely,erythrocytes (red),leukocytes (white),and platelets.Manual classification is time consuming and susceptible to error due to the different morphological features of the cells.This paper presents an intelligent system that simulates a human visual inspection and classification of the three blood cell types.The proposed system comprises two phases:The image preprocessing phase where blood cell features are extracted via global pattern averaging,and the neural network arbitration phase where training is the first and then classification is carried out.Experimental results suggest that the proposed method performs well in identifying blood cell types regardless of their irregular shapes,sizes and orientation,thus providing a fast,simple and efficient rotational and scale invariant blood cell identification system which can be used in automating laboratory reporting.

  12. Speech recognition systems on the Cell Broadband Engine

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y; Jones, H; Vaidya, S; Perrone, M; Tydlitat, B; Nanda, A

    2007-04-20

    In this paper we describe our design, implementation, and first results of a prototype connected-phoneme-based speech recognition system on the Cell Broadband Engine{trademark} (Cell/B.E.). Automatic speech recognition decodes speech samples into plain text (other representations are possible) and must process samples at real-time rates. Fortunately, the computational tasks involved in this pipeline are highly data-parallel and can receive significant hardware acceleration from vector-streaming architectures such as the Cell/B.E. Identifying and exploiting these parallelism opportunities is challenging, but also critical to improving system performance. We observed, from our initial performance timings, that a single Cell/B.E. processor can recognize speech from thousands of simultaneous voice channels in real time--a channel density that is orders-of-magnitude greater than the capacity of existing software speech recognizers based on CPUs (central processing units). This result emphasizes the potential for Cell/B.E.-based speech recognition and will likely lead to the future development of production speech systems using Cell/B.E. clusters.

  13. SBR-Blood: systems biology repository for hematopoietic cells.

    Science.gov (United States)

    Lichtenberg, Jens; Heuston, Elisabeth F; Mishra, Tejaswini; Keller, Cheryl A; Hardison, Ross C; Bodine, David M

    2016-01-01

    Extensive research into hematopoiesis (the development of blood cells) over several decades has generated large sets of expression and epigenetic profiles in multiple human and mouse blood cell types. However, there is no single location to analyze how gene regulatory processes lead to different mature blood cells. We have developed a new database framework called hematopoietic Systems Biology Repository (SBR-Blood), available online at http://sbrblood.nhgri.nih.gov, which allows user-initiated analyses for cell type correlations or gene-specific behavior during differentiation using publicly available datasets for array- and sequencing-based platforms from mouse hematopoietic cells. SBR-Blood organizes information by both cell identity and by hematopoietic lineage. The validity and usability of SBR-Blood has been established through the reproduction of workflows relevant to expression data, DNA methylation, histone modifications and transcription factor occupancy profiles. PMID:26590403

  14. Fuel cell using a hydrogen generation system

    Science.gov (United States)

    Dentinger, Paul M.; Crowell, Jeffrey A. W.

    2010-10-19

    A system is described for storing and generating hydrogen and, in particular, a system for storing and generating hydrogen for use in an H.sub.2/O.sub.2 fuel cell. The hydrogen storage system uses beta particles from a beta particle emitting material to degrade an organic polymer material to release substantially pure hydrogen. In a preferred embodiment of the invention, beta particles from .sup.63Ni are used to release hydrogen from linear polyethylene.

  15. 基于TD-LTE系统的小区间干扰抑制策略研究%Inter-cell Interference Suppression Strategy Based on TD-LTE Communication Systems

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    To solve the inter-cell interference problem in TD-LTE systems, a inter-cell interference suppression strategy is proposed based on game theory combination of uplink power control(UPC)and inter-cell interference coordination (ICIC)for TD-LTE communication systems. The main approach is divided into two steps. First, the users in the cell act as the game participants,and each user is assigned an appropriate identity of the player. Sec⁃ond, each player is assigned the UPC and ICIC algorithm makes its participation in the game,which can ultimate⁃ly inhibit the purpose of inter-cell interference and maximize system throughput.%  针对TD-LTE系统存在的小区间干扰问题,提出一种基于博弈论思想的结合上行链路功率控制(UPC)和小区间干扰协调(ICIC)的小区间干扰抑制策略:首先将小区中用户作为博弈参与者,为每个用户分配一个合适的游戏者身份;然后为每个游戏者分配合适的UPC和ICIC算法使其参与博弈,最终达到抑制小区间干扰,且最大化系统吞吐量的目的。

  16. Fuzzy control for the operation of an electrical energy generation system based on standard fuel cells PEM; Control difuso para la operacion de un sistema de generacion de energia electrica basado en celdas de combustible tipo PEM

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez R, Miguel; Gutierrez A, Ruben [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Rodriguez P, Alejandro [Centro Nacional de Investigacion y Desarrollo Tecnologico (Cenidet), Cuernavaca, Morelos (Mexico)

    2005-07-01

    Fuel cells, as totally clean power plants, have many applications in the industry in general, in the transport system, in the electricity generation for domestic consumption and in the communication systems, among others. When developing new forms of generation with renewable energy sources, it must be considered that petroleum will stop in being an available power resource. The interest in the study of the fuel cells has been increased in the last years because it is considered a solution to the supply of distributed energy problem. Therefore, already exist research institutions that are developing work on this technology. A generation of electrical energy system based on fuel cells is a nonlinear system where the control of the variables of the process, such as the temperature of the system and the pressurization of the reactants, are an important aspect for its proper operation, since it influences in the water balance and therefore in the global efficiency of the system. [Spanish] Las celdas de combustible, como fuente de energia totalmente limpia, tienen muchas aplicaciones en la industria en general: en el sistema de transporte, en la generacion de electricidad para consumo domestico y en los sistemas de comunicacion, entre otros. Al desarrollar nuevas formas de generacion con fuentes de energia renovables, se debe considerar que el petroleo dejara de ser un recurso energetico disponible. El interes en el estudio de las celdas de combustible se ha incrementado en los ultimos anos debido a que se le considera una solucion al problema de abasto de energia distribuida. Por lo tanto, ya existen instituciones de investigacion que estan desarrollando trabajos sobre esta tecnologia. Un sistema de generacion de energia electrica basado en celdas de combustible es un sistema no lineal en donde el control de las variables del proceso, tales como la temperatura del sistema y la presurizacion de los reactantes, es un aspecto importante para su buen funcionamiento, ya que

  17. Mesenchymal Stromal Cells as Cell-Based Therapeutics for Wound Healing

    OpenAIRE

    Samir Malhotra; Hu, Michael S.; Marshall, Clement D.; Tripp Leavitt; Alexander T. M. Cheung; Gonzalez, Jennifer G.; Harleen Kaur; Peter Lorenz, H.; Longaker, Michael T.

    2016-01-01

    Chronic wounds are a source of substantial morbidity for patients and are a major financial burden for the healthcare system. There are no current therapies that reliably improve nonhealing wounds or reverse pathological scarring. Mesenchymal stromal cells (MSCs) are a promising source of novel cell-based therapies due to the ease of their harvest and their integral role in the native wound repair process. Recent work has addressed the problems of loss of plasticity and off-target delivery th...

  18. Nanotechnology-based drug delivery systems

    Directory of Open Access Journals (Sweden)

    Singh Baljit

    2007-12-01

    Full Text Available Abstract Nanoparticles hold tremendous potential as an effective drug delivery system. In this review we discussed recent developments in nanotechnology for drug delivery. To overcome the problems of gene and drug delivery, nanotechnology has gained interest in recent years. Nanosystems with different compositions and biological properties have been extensively investigated for drug and gene delivery applications. To achieve efficient drug delivery it is important to understand the interactions of nanomaterials with the biological environment, targeting cell-surface receptors, drug release, multiple drug administration, stability of therapeutic agents and molecular mechanisms of cell signalling involved in pathobiology of the disease under consideration. Several anti-cancer drugs including paclitaxel, doxorubicin, 5-fluorouracil and dexamethasone have been successfully formulated using nanomaterials. Quantom dots, chitosan, Polylactic/glycolic acid (PLGA and PLGA-based nanoparticles have also been used for in vitro RNAi delivery. Brain cancer is one of the most difficult malignancies to detect and treat mainly because of the difficulty in getting imaging and therapeutic agents past the blood-brain barrier and into the brain. Anti-cancer drugs such as loperamide and doxorubicin bound to nanomaterials have been shown to cross the intact blood-brain barrier and released at therapeutic concentrations in the brain. The use of nanomaterials including peptide-based nanotubes to target the vascular endothelial growth factor (VEGF receptor and cell adhesion molecules like integrins, cadherins and selectins, is a new approach to control disease progression.

  19. Bringing fuel cells to reality and reality to fuel cells: A systems perspective on the use of fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Saxe, Maria

    2008-10-15

    The hopes and expectations on fuel cells are high and sometimes unrealistically positive. However, as an emerging technology, much remains to be proven and the proper use of the technology in terms of suitable applications, integration with society and extent of use is still under debate. This thesis is a contribution to the debate, presenting results from two fuel cell demonstration projects, looking into the introduction of fuel cells on the market, discussing the prospects and concerns for the near-term future and commenting on the potential use in a future sustainable energy system. Bringing fuel cells to reality implies finding near-term niche applications and markets where fuel cell systems may be competitive. In a sense fuel cells are already a reality as they have been demonstrated in various applications world-wide. However, in many of the envisioned applications fuel cells are far from being competitive and sometimes also the environmental benefit of using fuel cells in a given application may be questioned. Bringing reality to fuel cells implies emphasising the need for realistic expectations and pointing out that the first markets have to be based on the currently available technology and not the visions of what fuel cells could be in the future. The results from the demonstration projects show that further development and research on especially the durability for fuel cell systems is crucial and a general recommendation is to design the systems for high reliability and durability rather than striving towards higher energy efficiencies. When sufficient reliability and durability are achieved, fuel cell systems may be introduced in niche markets where the added values presented by the technology compensate for the initial high cost

  20. Ni-Based Solid Oxide Cell Electrodes

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg; Holtappels, Peter

    2013-01-01

    . The main emphasis will be on the following subjects: (a) electronic conductivity of cermets, (b) dimensional and thermodynamic stability including redox cycling, © thermal expansion coefficient matching, (d) chemical compatibility with stack components and gaseous reactants and (e) electrode reaction......This paper is a critical review of the literature on nickel-based electrodes for application in solid oxide cells at temperature from 500 to 1000 _C. The applications may be fuel cells or electrolyser cells. The reviewed literature is that of experimental results on both model electrodes...... and practical composite cermet electrodes. A substantially longer three-phase boundary (TPB) can be obtained per unit area of cell in such a composite of nickel and electrolyte material, provided that two interwoven solid networks of the two solid and one gaseous phases are obtained to provide a three...

  1. Solar regenerative fuel cell system for high altitude airships

    International Nuclear Information System (INIS)

    'Full text': A closed-loop regenerative fuel cell (RFC) system that serves as an energy storage device for space activities is studied through dynamic simulations. The unique nature of the closed-loop RFC makes it an ideal power system for key applications in homeland defense and earth observatory systems such as high altitude aircrafts /airships, unmanned aerial vehicles, and in planetary exploration for flyer or for surface power. The RFC considered using the photovoltaic cells to produce electric power during the day, part of which is used to produce hydrogen and oxygen through electrolysis. The stored hydrogen and oxygen is used through a fuel cell to produce electric power during night hours. A MATLAB/SIMULINK model was developed for the components of the RFC that include a fuel cell, electrolyzer, photovoltaic solar array, power bus, humidifiers, compressor/motor assembly, expander, pumps, phase separators, storage tanks for hydrogen, oxygen and water, control valves and piping, electric grid system and controls. A proton exchange membrane (PEM) fuel cell and PEM electrolyzer were modeled in detail that included the mass momentum, energy, chemical reaction rates at cathode and anode. The PEM fuel cell voltage was modeled accounting cell activation and ohmic polarizations. A modular approach was used to develop models for each component. Component models were based on fundamental physics to the extent practical. Steady state and dynamic response of the RFC for different operational conditions including start-up, shut down, load changes and (accidental) transients was studied. (author)

  2. Solid oxide fuel cell power system development

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, Rick [Delphi Automotive Systems, LLC., Troy, MI (United States); Wall, Mark [Independent Energy Partners Technology, LLC., Parker, CO (United States); Sullivan, Neal [Colorado School of Mines, Golden, CO (United States)

    2015-06-26

    This report summarizes the progress made during this contractual period in achieving the goal of developing the solid oxide fuel cell (SOFC) cell and stack technology to be suitable for use in highly-efficient, economically-competitive, commercially deployed electrical power systems. Progress was made in further understanding cell and stack degradation mechanisms in order to increase stack reliability toward achieving a 4+ year lifetime, in cost reduction developments to meet the SECA stack cost target of $175/kW (in 2007 dollars), and in operating the SOFC technology in a multi-stack system in a real-world environment to understand the requirements for reliably designing and operating a large, stationary power system.

  3. Microfabricated Electrochemical Cell-Based Biosensors for Analysis of Living Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2012-04-01

    Full Text Available Cellular biochemical parameters can be used to reveal the physiological and functional information of various cells. Due to demonstrated high accuracy and non-invasiveness, electrochemical detection methods have been used for cell-based investigation. When combined with improved biosensor design and advanced measurement systems, the on-line biochemical analysis of living cells in vitro has been applied for biological mechanism study, drug screening and even environmental monitoring. In recent decades, new types of miniaturized electrochemical biosensor are emerging with the development of microfabrication technology. This review aims to give an overview of the microfabricated electrochemical cell-based biosensors, such as microelectrode arrays (MEA, the electric cell-substrate impedance sensing (ECIS technique, and the light addressable potentiometric sensor (LAPS. The details in their working principles, measurement systems, and applications in cell monitoring are covered. Driven by the need for high throughput and multi-parameter detection proposed by biomedicine, the development trends of electrochemical cell-based biosensors are also introduced, including newly developed integrated biosensors, and the application of nanotechnology and microfluidic technology.

  4. MMS Based Car Security System

    Directory of Open Access Journals (Sweden)

    Surendra Sot

    2013-03-01

    Full Text Available In This paper “MMS Based Car Security System” is being proposed to solve the issue. It introduces the integration between monitoring and tracking system. Both elements are very crucial in order to have a powerful security system. The system can send SMS and MMS to the owner to have fast response especially if the car is nearby. This paper focuses on using MMS and SMS technology. As soon as there is intrusion detected, first the SMS is sent to master user and the picture of the intruder will be sent via local GSM/GPRS service provider to user (and / or police mail ID. The implementation and testing results show the success of prototype in sending MMS to owner within 30 seconds. The timing and results are suitable to owner and police to take suitable action against intruder. User can also control the module using command. User has to send different SMS to module while configuration of module for master. Master user can be change as per need, only master user can make changes in to the module.

  5. MEMS-based thin-film fuel cells

    Science.gov (United States)

    Jankowksi, Alan F.; Morse, Jeffrey D.

    2003-10-28

    A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

  6. Study of a potential drug delivery system based on carbon nanoparticles: effects of fullerene derivatives in MCF7 mammary carcinoma cells

    International Nuclear Information System (INIS)

    Fullerenes (C60) represent important carbon nanoparticles, widely investigated for diagnostic and therapeutic uses, mainly because they are characterized by a small size (between 7 and 10 Å) and a large surface area. The cytotoxicity of two fullerene derivatives, functionalized by 1,3-dipolar cycloaddition of azomethine ylides to the C60 cage (1 and 2), the mechanism of cellular uptake (studied with a fluorescein-bearing derivative of 1, hereafter called derivative 3), and the intracellular distribution are the subject of this work. Cell cytotoxicity on human mammary carcinoma cell line (MCF7), evaluated with the MTT test and further confirmed by a flow cytometry approach with DiOC6 and PI probes, showed that derivative 1 was free of necrotic or apoptotic effects even after a long lasting cell exposure. Cell uptake and internalization of derivative 3 reach their zenith within 12 h after treatment, with a tendency to persist up to 72 h; this process was evaluated by flow cytometry and confirmed by confocal microscopy. Thus, it appears that a compound such as derivative 1 may be unspecifically taken up by MCF7 cells, in which it distributes throughout the cytoplasm, apparently avoiding any co-localization within the nucleus and secretory granules. These results suggest a strong interaction between the tested fullerene and mammalian cells and a significant ability of this compound to enter tumor cells, therefore resulting to be a suitable vector to deliver anticancer agents to tumor cells.

  7. Automotive Fuel Processor Development and Demonstration with Fuel Cell Systems

    Energy Technology Data Exchange (ETDEWEB)

    Nuvera Fuel Cells

    2005-04-15

    processor subsystems (fuel reformer, CO cleanup, and exhaust cleanup) that were small enough to integrate on a vehicle and (2) evaluating the fuel processor system performance for hydrogen production, efficiency, thermal integration, startup, durability and ability to integrate with fuel cells. Nuvera carried out a three-part development program that created multi-fuel (gasoline, ethanol, natural gas) fuel processing systems and investigated integration of fuel cell / fuel processor systems. The targets for the various stages of development were initially based on the goals of the DOE's Partnership for New Generation Vehicles (PNGV) initiative and later on the Freedom Car goals. The three parts are summarized below with the names based on the topic numbers from the original Solicitation for Financial Assistance Award (SFAA).

  8. Multipotenciostat System Based on Virtual Instrumentation

    Directory of Open Access Journals (Sweden)

    Arrieta-Almario Álvaro Angel

    2014-07-01

    Full Text Available To carry out this project an electronic multichannel system of electrochemical measurement or multipotenciostat was developed. It is based on the cyclic voltammetry measurement technique, controlled by a computer that monitors, by means of an electronic circuit, both the voltage generated from the Pc and supplied to an electrolytic cell, and the current that flows through the electrodes of it. To design the application software and the user interface, Virtual Instrumentation was used. On the other hand, to perform the communication between the multipotenciostat circuit and the designed software, the National Instruments NI9263 and NI9203 acquisition modules were used. The system was tested on a substance with a known REDOX property, as well as to discriminate and classify some samples of coffee.

  9. Multiphysics Based Thermal Modeling of a Pouch Lithium-Ion Battery Cell for the Development of Pack Level Thermal Management System

    DEFF Research Database (Denmark)

    Khan, Mohammad Rezwan; Kær, Søren Knudsen

    2016-01-01

    The research is focused on the development of a three-dimensional cell level multiphysics battery thermal model. The primary aim is to represent the cooling mechanism inside the unit cell battery pack. It is accomplished through the coupling of heat transfer and computational fluid dynamics (CFD)......-temporal behavior of Li-ion battery in different operating conditions.......The research is focused on the development of a three-dimensional cell level multiphysics battery thermal model. The primary aim is to represent the cooling mechanism inside the unit cell battery pack. It is accomplished through the coupling of heat transfer and computational fluid dynamics (CFD......) physics. A lumped value of heat generation (HG) inside the battery cell is used. It stems from isothermal calorimeter experiment. HG depends on current rate and the corresponding operating temperature. It is demonstrated that the developed model provides a deeper understanding of the thermal spatio...

  10. A Correlation-Based Fingerprint Verification System

    NARCIS (Netherlands)

    Bazen, Asker M.; Verwaaijen, Gerben T.B.; Gerez, Sabih H.; Veelenturf, Leo P.J.; Zwaag, van der Berend Jan

    2000-01-01

    In this paper, a correlation-based fingerprint verification system is presented. Unlike the traditional minutiae-based systems, this system directly uses the richer gray-scale information of the fingerprints. The correlation-based fingerprint verification system first selects appropriate templates i

  11. Fabrication and Characterization of Copper System Compound Semiconductor Solar Cells

    Directory of Open Access Journals (Sweden)

    Ryosuke Motoyoshi

    2010-01-01

    Full Text Available Copper system compound semiconductor solar cells were produced by a spin-coating method, and their cell performance and structures were investigated. Copper indium disulfide- (CIS- based solar cells with titanium dioxide (TiO2 were produced on F-doped SnO2 (FTO. A device based on an FTO/CIS/TiO2 structure provided better cell performance compared to that based on FTO/TiO2/CIS structure. Cupric oxide- (CuO- and cuprous oxide- (Cu2O- based solar cells with fullerene (C60 were also fabricated on FTO and indium tin oxide (ITO. The microstructure and cell performance of the CuO/C60 heterojunction and the Cu2O:C60 bulk heterojunction structure were investigated. The photovoltaic devices based on FTO/CuO/C60 and ITO/Cu2O:C60 structures provided short-circuit current density of 0.015 mAcm−2 and 0.11 mAcm−2, and open-circuit voltage of 0.045 V and 0.17 V under an Air Mass 1.5 illumination, respectively. The microstructures of the active layers were examined by X-ray diffraction and transmission electron microscopy.

  12. Decision Support and Knowledge-Based Systems.

    Science.gov (United States)

    Konsynski, Benn R.; And Others

    1988-01-01

    A series of articles addresses issues concerning decision support and knowledge based systems. Topics covered include knowledge-based systems for information centers; object oriented systems; strategic information systems case studies; user perception; manipulation of certainty factors by individuals and expert systems; spreadsheet program use;…

  13. Electrospinning Nanofiber Based Organic Solar Cell

    Science.gov (United States)

    Yang, Zhenhua; Liu, Ying; Moffa, Maria; Nam, Chang-Yong; Pisignano, Dario; Rafailovich, Miriam

    Bulk heterojunction (BHJ) polymer solar cells are an area of intense interest due to their potential to result in printable, inexpensive solar cells which can be processed onto flexible substrates. The active layer is typically spin coated from the solution of polythiophene derivatives (donor) and fullerenes (acceptor) and interconnected domains are formed because of phase separation. However, the power conversion efficiency (PCE) of BHJ solar cell is restricted by the presence of unfavorable morphological features, including dead ends or isolated domains. Here we MEH-PPV:PVP:PCBM electrospun nanofiber into BHJ solar cell for the active layer morphology optimization. Larger interfacial area between donor and acceptor is abtained with electrospinning method and the high aspect ratio of the MEH-PPV:PVP:PCBM nanofibers allow them to easily form a continuous pathway. The surface morphology is investigated with atomic force microscopy (AFM) and scanning electron microscopy (SEM). Electrospun nanofibers are discussed as a favorable structure for application in bulk-heterojunction organic solar cells. Electrospinning Nanofiber Based Bulk Heterojunction Organic Solar Cell.

  14. 菲涅耳聚光系统下砷化镓电池输出特性研究%Investigation of the Output Characteristics of GaAs Solar Cell Based on Fresnel Concentrating System

    Institute of Scientific and Technical Information of China (English)

    王文博; 李明; 季旭; 魏生贤; 王六玲; 杨玉文; 范介清; 龙星

    2012-01-01

    The output characteristics on a GaAs solar cell and the components which are composed of six pieces of GaAs solar cells in concentration ratio 676 based on Fresnel concentrating system is analyzed. Single-index model of GaAs solar cell is established and compared with experiments. There is a good agreement of theory and experiments with the error less than 7.6%. The experimental results indicate that, with the same concentration ratio, a GaAs solar cell is in concentration ratio 390, and the six pieces of GaAs solar cells is in concentration ratio 281. The short-circuit current of the monolithic cell is enlarged 322 times, and the max electric power is enlarged 316 times in concentration which of the six pieces of GaAs solar cells system is enlarged 275 times and 272 times. The maximum power output of the solar cell is achieved when the energy-flux density is 0.321 MW/tn2. The GaAs solar cell works well with a temperature lower than 323 K. The efficiency of the system increases 0.227% as the transmittance of the system improve 0.01. The monolithic GaAs solar cell can generate electric energy 0.015 kW?hand the the cell set of six pieces can generate electric energy 0.076 kW-h for a clear day with daily direct irradiation of 17. 212 MJ/m2.%对理论聚光比为676的菲涅耳聚光系统下单片砷化镓太阳电池及由六片砷化镓电池的串联组件的输出特性进行分析.建立三结砷化镓电池输出特性的单指数数学模型,并与实验进行了对比.理论计算与实验吻合较好,误差在7.6%以内.实验结果表明,在相同理论聚光比下,单片电池系统能流聚光比为390,六片电池组件系统能流聚光比为281;聚光后单片电池的短路电流与峰值功率分别放大322倍与316倍,六片电池组件系统的短路电流与峰值功率分别放大275倍与272倍;电池表面能流密度为0.321 MW/m2时电池的输出功率达到最大,电池表面温度高于323 K将影响其工作稳定性;聚

  15. Liquid Crystal Cells Based on Photovoltaic Substrates

    Science.gov (United States)

    Lucchetti, L.; Kushnir, K.; Zaltron, A.; Simoni, F.

    2016-02-01

    Liquid crystal cells with LiNbO3:Fe crystals as substrates, are described. The photovoltaic field generated by the substrates is able to reorient the liquid crystal director thus giving rise to a phase shift on the light propagating through the cell, as in liquid crystal light valves. The process does not require the application of an external electric field, thus being potentially useful for applications requiring a high degree of compactness. An efficient optical switch with a high transmission contrast, based on the described optically-induced electric field, is also proposed.

  16. Automated microinjection system for adherent cells

    Science.gov (United States)

    Youoku, Sachihiro; Suto, Yoshinori; Ando, Moritoshi; Ito, Akio

    2007-07-01

    We have developed an automated microinjection system that can handle more than 500 cells an hour. Microinjection injects foreign agents directly into cells using a micro-capillary. It can randomly introduce agents such as DNA, proteins and drugs into various types of cells. However, conventional methods require a skilled operator and suffer from low throughput. The new automated microinjection techniques we have developed consist of a Petri dish height measuring method and a capillary apex position measuring method. The dish surface height is measured by analyzing the images of cells that adhere to the dish surface. The contrast between the cell images is minimized when the focus plane of an object lens coincides with the dish surface. We have developed an optimized focus searching method with a height accuracy of +/-0.2 um. The capillary apex position detection method consists of three steps: rough, middle, and precise. These steps are employed sequentially to cover capillary displacements of up to +/-2 mm, and to ultimately accomplish an alignment accuracy of less than one micron. Experimental results using this system we developed show that it can introduce fluorescent material (Alexa488) into adherent cells, HEK293, with a success rate of 88.5%.

  17. Honeypot based Secure Network System

    Directory of Open Access Journals (Sweden)

    Yogendra Kumar Jain

    2011-02-01

    Full Text Available A honeypot is a non-production system, design to interact with cyber-attackers to collect intelligence on attack techniques and behaviors. There has been great amount of work done in the field of networkintrusion detection over the past three decades. With networks getting faster and with the increasing dependence on the Internet both at the personal and commercial level, intrusion detection becomes a challenging process. The challenge here is not only to be able to actively monitor large numbers of systems, but also to be able to react quickly to different events. Before deploying a honeypot it is advisable to have a clear idea of what the honeypot should and should not do. There should be clear understandingof the operating systems to be used and services (like a web server, ftp server etc a honeypot will run. The risks involved should be taken into consideration and methods to tackle or reduce these risks should be understood. It is also advisable to have a plan on what to do should the honeypot be compromised. In case of production honeypots, a honeypot policy addressing security issues should be documented. Any legal issues with respect to the honeypots or their functioning should also be taken into consideration. In this paper we explain the relatively new concept of “honeypot.” Honeypots are a computer specifically designed to help learn the motives, skills and techniques of the hacker community and also describes in depth the concepts of honeypots and their contribution to the field of network security. The paper then proposes and designs an intrusion detection tool based on some of the existing intrusion detection techniques and the concept of honeypots.

  18. Expert systems and computer based industrial systems

    International Nuclear Information System (INIS)

    Framentec is the artificial intelligence subsidiary of FRAMATOME. It is involved in expert-system activities of Shells, developments, methodology and software for maintenance (Maintex) and consulting and methodology. Specific applications in the nuclear field are presented. The first is an expert system to assist in the piping support design prototype, the second is an expert system that assists an ultrasonic testing operator in determining the nature of a welding defect and the third is a welding machine diagnosis advisor. Maintex is a software tool to provide assistance in the repair of complex industrial equipment. (author)

  19. Fuel cell technology for prototype logistic fuel cell mobile systems

    Energy Technology Data Exchange (ETDEWEB)

    Sederquist, R.A.; Garow, J.

    1995-08-01

    Under the aegis of the Advanced Research Project Agency`s family of programs to develop advanced technology for dual use applications, International Fuel Cells Corporation (IFC) is conducting a 39 month program to develop an innovative system concept for DoD Mobile Electric Power (MEP) applications. The concept is to integrate two technologies, the phosphoric acid fuel cell (PAFC) with an auto-thermal reformer (ATR), into an efficient fuel cell power plant of nominally 100-kilowatt rating which operates on logistic fuels (JP-8). The ATR fuel processor is the key to meeting requirements for MEP (including weight, volume, reliability, maintainability, efficiency, and especially operation on logistic fuels); most of the effort is devoted to ATR development. An integrated demonstration test unit culminates the program and displays the benefits of the fuel cell system, relative to the standard 100-kilowatt MEP diesel engine generator set. A successful test provides the basis for proceeding toward deployment. This paper describes the results of the first twelve months of activity during which specific program aims have remained firm.

  20. Sizing an isolated wind-solar-fuel cell generation system based on the particle swarm optimization method; Dimensionamiento de un sistema de generacion aislado eolico-solar-celda de combustible basado en el metodo de optimizacion de enjambre de particulas

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Huerta, V; Ramirez-Arredondo, Juan M. [Universidad de Quintana Roo, Chetumal, Quintana Roo (Mexico)]. E-mail: vsanchez@gdl.cinvestav.mx; Arriaga-Hurtado, L. G. [CIDETEQ, Queretaro (Mexico)

    2009-09-15

    Sizing an electric energy system requires an analysis of investment, maintenance and operating costs. In the case of a generation system that uses renewable sources, optimal capacity becomes more complex compared to a conventional system, because of the randomness of renewable resources (wind, solar) and the still high costs of wind and photovoltage generator modules. This work presents the optimal sizing of a wind-solar-fuel cell generation system, minimizing the costs of the system while satisfying the energy demands of an isolated charge. The optimization method used is based on an evolutionary programming technique known as particle swarms (PSO-particle swarm optimization). The generation of energy with a hybrid system is discussed, based on the profile of insolation and wind availability at the site, with the objective of satisfying a specific electric demand. [Spanish] El dimensionamiento de un sistema de generacion de energia electrica requiere un analisis de los costos de inversion, mantenimiento y operacion. En el caso de un sistema de generacion que utiliza fuentes renovables la capacidad optima resulta mas compleja con respecto a un sistema convencional, debido a la aleatoriedad de los recursos renovables (eolico, solar), y a los aun altos costos de generadores eolicos y modulos fotovoltaicos. En este trabajo se presenta el dimensionamiento optimo de un sistema de generacion eolico-solar-celda de combustible minimizando los costos del sistema que satisfaga la energia demandada por una carga aislada. El metodo de optimizacion utilizado esta basado en una tecnica de programacion evolutiva conocida como enjambre de particulas (PSO por sus siglas en ingles: particle swarm optimization). Se plantea la generacion de energia del sistema hibrido con base a la insolacion y el perfil del viento disponible en sitio, con objeto de satisfacer una demanda electrica determinada.

  1. Examination of the effect of system pressure ratio and heat recuperation on the efficiency of a coal based gas turbine fuel cell hybrid power generation system with CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    VanOsdol, J.G.; Gemmen, R.S.; Liese, E.A

    2008-06-01

    This paper examines two coal-based hybrid configurations that employ separated anode and cathode streams for the capture and compression of CO2. One configuration uses a standard Brayton cycle, and the other adds heat recuperation ahead of the fuel cell. Results show that peak efficiencies near 55% are possible, regardless of cycle configuration, including the cost in terms of energy production of CO2 capture and compression. The power that is required to capture and compress the CO2 is shown to be approximately 15% of the total plant power.

  2. Fuel quality issues in stationary fuel cell systems.

    Energy Technology Data Exchange (ETDEWEB)

    Papadias, D.; Ahmed, S.; Kumar, R. (Chemical Sciences and Engineering Division)

    2012-02-07

    Fuel cell systems are being deployed in stationary applications for the generation of electricity, heat, and hydrogen. These systems use a variety of fuel cell types, ranging from the low temperature polymer electrolyte fuel cell (PEFC) to the high temperature solid oxide fuel cell (SOFC). Depending on the application and location, these systems are being designed to operate on reformate or syngas produced from various fuels that include natural gas, biogas, coal gas, etc. All of these fuels contain species that can potentially damage the fuel cell anode or other unit operations and processes that precede the fuel cell stack. These detrimental effects include loss in performance or durability, and attenuating these effects requires additional components to reduce the impurity concentrations to tolerable levels, if not eliminate the impurity entirely. These impurity management components increase the complexity of the fuel cell system, and they add to the system's capital and operating costs (such as regeneration, replacement and disposal of spent material and maintenance). This project reviewed the public domain information available on the impurities encountered in stationary fuel cell systems, and the effects of the impurities on the fuel cells. A database has been set up that classifies the impurities, especially in renewable fuels, such as landfill gas and anaerobic digester gas. It documents the known deleterious effects on fuel cells, and the maximum allowable concentrations of select impurities suggested by manufacturers and researchers. The literature review helped to identify the impurity removal strategies that are available, and their effectiveness, capacity, and cost. A generic model of a stationary fuel-cell based power plant operating on digester and landfill gas has been developed; it includes a gas processing unit, followed by a fuel cell system. The model includes the key impurity removal steps to enable predictions of impurity breakthrough

  3. Synthesis of Evolving Cells for Reconfigurable Manufacturing Systems

    Science.gov (United States)

    Padayachee, J.; Bright, G.

    2014-07-01

    The concept of Reconfigurable Manufacturing Systems (RMSs) was formulated due to the global necessity for production systems that are able to economically evolve according to changes in markets and products. Technologies and design methods are under development to enable RMSs to exhibit transformable system layouts, reconfigurable processes, cells and machines. Existing factory design methods and software have not yet advanced to include reconfigurable manufacturing concepts. This paper presents the underlying group technology framework for the design of manufacturing cells that are able to evolve according to a changing product mix by mechanisms of reconfiguration. The framework is based on a Norton- Bass forecast and time variant BOM models. An adaptation of legacy group technology methods is presented for the synthesis of evolving cells and two optimization problems are presented within this context.

  4. Temperature dependent estimator for load cells using an adaptive neuro-fuzzy inference system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K-C [Department of Automation Engineering, National Formosa University, Huwei, Yunlin 63208, Taiwan (China)

    2005-01-01

    Accurate weighting of pieces in various temperature environments for load cells is a key feature in many industrial applications. This paper proposes a method to achieve high-precision {+-}0.56/3000 grams for a load-cell-based weighting system by using ANFIS. ANFIS is used to model the relationship between the reading of load cells and the actual weight of samples considering temperature-varying effect and nonlinearity of the load cells. The model of the load-cell-based weighting system can accurately estimate the weight of test samples from the load cell reading. The proposed ANFIS-based method is convenient for use and can improve the precision of digital load cell measurement systems. Experiments demonstrate the validity and effectiveness of fuzzy neural networks for modeling of load cells and the results show that the proposed ANFIS-based method outperforms some existing methods in terms of modeling and prediction accuracy.

  5. Fuel Cell System for Transportation -- 2005 Cost Estimate

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, D.

    2006-10-01

    Independent review report of the methodology used by TIAX to estimate the cost of producing PEM fuel cells using 2005 cell stack technology. The U.S. Department of Energy (DOE) Hydrogen, Fuel Cells and Infrastructure Technologies Program Manager asked the National Renewable Energy Laboratory (NREL) to commission an independent review of the 2005 TIAX cost analysis for fuel cell production. The NREL Systems Integrator is responsible for conducting independent reviews of progress toward meeting the DOE Hydrogen Program (the Program) technical targets. An important technical target of the Program is the proton exchange membrane (PEM) fuel cell cost in terms of dollars per kilowatt ($/kW). The Program's Multi-Year Program Research, Development, and Demonstration Plan established $125/kW as the 2005 technical target. Over the last several years, the Program has contracted with TIAX, LLC (TIAX) to produce estimates of the high volume cost of PEM fuel cell production for transportation use. Since no manufacturer is yet producing PEM fuel cells in the quantities needed for an initial hydrogen-based transportation economy, these estimates are necessary for DOE to gauge progress toward meeting its targets. For a PEM fuel cell system configuration developed by Argonne National Laboratory, TIAX estimated the total cost to be $108/kW, based on assumptions of 500,000 units per year produced with 2005 cell stack technology, vertical integration of cell stack manufacturing, and balance-of-plant (BOP) components purchased from a supplier network. Furthermore, TIAX conducted a Monte Carlo analysis by varying ten key parameters over a wide range of values and estimated with 98% certainty that the mean PEM fuel cell system cost would be below DOE's 2005 target of $125/kW. NREL commissioned DJW TECHNOLOGY, LLC to form an Independent Review Team (the Team) of industry fuel cell experts and to evaluate the cost estimation process and the results reported by TIAX. The results of

  6. System design impacts on optimization of the advanced radioisotope power system (ARPS) AMTEC cell

    International Nuclear Information System (INIS)

    Several NASA deep space missions require Advanced Radioisotope Power Systems (ARPS) to supply spacecraft power for various internal functions and mission instruments and experiments. AMTEC (Alkali-Metal Thermal-Electric Conversion) power conversion is the DOE-selected technology for an advanced, next- generation RPS to power these spacecraft. Advanced Modular Power Systems, Inc. (AMPS) has begun investigating the design of an AMTEC-based ARPS using the General Purpose Heat Source (GPHS) and the latest PX-5 AMTEC cell technology with refractory materials in critical components. This paper presents and discusses the system design methodology, and results of important system design tradeoffs and system design impacts on the ARPS AMTEC cell design. This work investigated dual 2-GPHS system configurations and 4-GPHS system configurations with 16 side-mounted AMTEC cells operating at beginning-of-mission (BOM) and end-of-mission (EOM) GPHS heat dissipation conditions. Current design studies indicate using a refractory material AMTEC cell with 8-BASE tubes, 5.0 inches long, and 1.75 inches diameter in the 4-GPHS system configuration is the strongest design candidate to satisfy system performance requirements

  7. The large-scale digital cell analysis system: an open system for nonperturbing live cell imaging.

    Science.gov (United States)

    Davis, Paul J; Kosmacek, Elizabeth A; Sun, Yuansheng; Ianzini, Fiorenza; Mackey, Michael A

    2007-12-01

    The Large-Scale Digital Cell Analysis System (LSDCAS) was designed to provide a highly extensible open source live cell imaging system. Analysis of cell growth data has demonstrated a lack of perturbation in cells imaged using LSDCAS, through reference to cell growth data from cells growing in CO(2) incubators. LSDCAS consists of data acquisition, data management and data analysis software, and is currently a Core research facility at the Holden Comprehensive Cancer Center at the University of Iowa. Using LSDCAS analysis software, this report and others show that although phase-contrast imaging has no apparent effect on cell growth kinetics and viability, fluorescent image acquisition in the cell lines tested caused a measurable level of growth perturbation using LSDCAS. This report describes the current design of the system, reasons for the implemented design, and details its basic functionality. The LSDCAS software runs on the GNU/Linux operating system, and provides easy to use, graphical programs for data acquisition and quantitative analysis of cells imaged with phase-contrast or fluorescence microscopy (alone or in combination), and complete source code is freely available under the terms of the GNU Public Software License at the project website (http://lsdcas.engineering.uiowa.edu). PMID:18045324

  8. A case study analysis of system efficiency, viability and energy values of SOFC based fuel cell Micro-CHP for office buildings

    OpenAIRE

    Tesfai, Alem; Mylona, A.; Connor, Paul Alexander; Cassidy, Mark; Irvine, John Thomas Sirr

    2015-01-01

    The built environment is a large contributor to the greenhouse gas emissions. The first step in tackling environmental impact and fuel cost reduction is the minimization of energy losses through introduction of new and more efficient energy conversion technologies. In this study, the potential application of fuel cell micro-CHP in a typical office building is investigated. A 1.5 kWel fuel cell micro-CHP has been installed in an office building at CIBSE headquarters (HQ). The unit converts nat...

  9. A human stem cell-based model for identifying adverse effects of organic and inorganic chemicals on the developing nervous system

    DEFF Research Database (Denmark)

    Buzanska, Leonora; Sypecka, Joanna; Nerini-Molteni, Silvia;

    2009-01-01

    (sodium tellurite, methylmercury chloride, cadmium chloride, chlorpyrifos, and L-glutamate) and non-neurotoxic (acetaminophen, theophylline, and D-glutamate) compounds. In addition, we investigated the effect of some compounds on key neurodevelopmental processes like cell proliferation, apoptotic cell...... death, and neuronal and glial differentiation. Less differentiated HUCB-NSCs were generally more sensitive to neurotoxicants, with the notable exception of L-glutamate, which showed a higher toxicity to later stages. The relative potencies of the compounds were: cadmium chloride > methylmercury chloride...

  10. The promise of fuel cell-based automobiles

    Indian Academy of Sciences (India)

    A K Shukla; C L Jackson; K Scott

    2003-02-01

    Fuel cell-based automobiles have gained attention in the last few years due to growing public concern about urban air pollution and consequent environmental problems. From an analysis of the power and energy requirements of a modern car, it is estimated that a base sustainable power of $ca$. 50 kW supplemented with short bursts up to 80 kW will suffice in most driving requirements. The energy demand depends greatly on driving characteristics but under normal usage is expected to be 200 Wh/km. The advantages and disadvantages of candidate fuel-cell systems and various fuels are considered together with the issue of whether the fuel should be converted directly in the fuel cell or should be reformed to hydrogen onboard the vehicle. For fuel cell vehicles to compete successfully with conventional internal-combustion engine vehicles, it appears that direct conversion fuel cells using probably hydrogen, but possibly methanol, are the only realistic contenders for road transportation applications. Among the available fuel cell technologies, polymer–electrolyte fuel cells directly fueled with hydrogen appear to be the best option for powering fuel cell vehicles as there is every prospect that these will exceed the performance of the internal-combustion engine vehicles but for their first cost. A target cost of $ 50/kW would be mandatory to make polymer–electrolyte fuel cells competitive with the internal combustion engines and can only be achieved with design changes that would substantially reduce the quantity of materials used. At present, prominent car manufacturers are deploying important research and development efforts to develop fuel cell vehicles and are projecting to start production by 2005.

  11. Efficacy and limitations of an ATP-based monitoring system.

    Science.gov (United States)

    Turner, Danielle E; Daugherity, Erin K; Altier, Craig; Maurer, Kirk J

    2010-03-01

    Monitoring of sanitation is an essential function of laboratory animal facilities. The purpose of the current study was to assess the ability of an ATP-based system to detect microbes and organic contaminants. Serial dilutions of Escherichia coli, Staphylococcus aureus, Toxocara canis eggs, Toxoplasma gondii tachyzoites, epithelial cells, and rodent blood, urine, and feces were analyzed according to the manufacturer's recommendations. The limit of E. coli detection was 10(4) organisms; sonication of E. coli significantly improved detection, indicating incomplete bacterial lysis in the detection system. Detection of S. aureus was significantly greater than that of E. coli with a limit of detection of 10(2); sonication did not alter results. In contrast, detection of T. canis, T. gondii, RBC, and epithelial cells was robust and ranged from 2 T. canis eggs to 10 epithelial cells. Urine was weakly detected, with a limit of detection at 1:10 dilution. Detection of all cell types except epithelia had a strong linear correlation to total cell number. In addition, our data demonstrate that the efficacy of the detection system can be affected adversely by residual disinfectants and that sample-bearing swabs are stable for more than 7 h after swabbing. These data demonstrate that this ATP based system sensitively detects pure cells and organic contaminants with a strong degree of linear predictability. A limitation of the system is its inability to detect gram-negative bacteria efficiently because of incomplete cell lysis. PMID:20353694

  12. SQUID-based measuring systems

    Indian Academy of Sciences (India)

    M P Janawadkar; R Baskaran; R Nagendran; K Gireesan; N Harishkumar; Rita Saha; L S Vaidhyanathan; J Jayapandian; Y Hariharan; T S Radhakrishnan

    2002-05-01

    A program has been developed and initiated at the Indira Gandhi Centre for Atomic Research (IGCAR) for the utilization of SQUID sensors in various application areas. DC SQUID sensors based on Nb–AlO–Nb Josephson junctions have been designed and developed inhouse along with associated flux-locked loop (FLL) electronics. A compact low field SQUID magnetometer insertible in a liquid helium storage dewar has also been developed inhouse and is in use. Efforts to build a high field SQUID magnetometer, SQUID-DAC system, are in progress. A planar gradiometric DC SQUID sensor for non-destructive evaluation (NDE) application to be used in relatively unshielded environment has been designed and developed. An easily portable NDE cryostat with a small lift-off distance, to be used in external locations has been designed and tested. The magnetic field produced by a given two-dimensional current density distribution is inverted using the Fourier transform technique.

  13. Organic electrochemical transistors for cell-based impedance sensing

    Science.gov (United States)

    Rivnay, Jonathan; Ramuz, Marc; Leleux, Pierre; Hama, Adel; Huerta, Miriam; Owens, Roisin M.

    2015-01-01

    Electrical impedance sensing of biological systems, especially cultured epithelial cell layers, is now a common technique to monitor cell motion, morphology, and cell layer/tissue integrity for high throughput toxicology screening. Existing methods to measure electrical impedance most often rely on a two electrode configuration, where low frequency signals are challenging to obtain for small devices and for tissues with high resistance, due to low current. Organic electrochemical transistors (OECTs) are conducting polymer-based devices, which have been shown to efficiently transduce and amplify low-level ionic fluxes in biological systems into electronic output signals. In this work, we combine OECT-based drain current measurements with simultaneous measurement of more traditional impedance sensing using the gate current to produce complex impedance traces, which show low error at both low and high frequencies. We apply this technique in vitro to a model epithelial tissue layer and show that the data can be fit to an equivalent circuit model yielding trans-epithelial resistance and cell layer capacitance values in agreement with literature. Importantly, the combined measurement allows for low biases across the cell layer, while still maintaining good broadband signal.

  14. Organic electrochemical transistors for cell-based impedance sensing

    Energy Technology Data Exchange (ETDEWEB)

    Rivnay, Jonathan, E-mail: rivnay@emse.fr, E-mail: owens@emse.fr; Ramuz, Marc; Hama, Adel; Huerta, Miriam; Owens, Roisin M., E-mail: rivnay@emse.fr, E-mail: owens@emse.fr [Department of Bioelectronics, Ecole des Mines de St. Etienne, 13541 Gardanne (France); Leleux, Pierre [Department of Bioelectronics, Ecole des Mines de St. Etienne, 13541 Gardanne (France); Microvitae Technologies, Pole d' Activite Y. Morandat, 13120 Gardanne (France)

    2015-01-26

    Electrical impedance sensing of biological systems, especially cultured epithelial cell layers, is now a common technique to monitor cell motion, morphology, and cell layer/tissue integrity for high throughput toxicology screening. Existing methods to measure electrical impedance most often rely on a two electrode configuration, where low frequency signals are challenging to obtain for small devices and for tissues with high resistance, due to low current. Organic electrochemical transistors (OECTs) are conducting polymer-based devices, which have been shown to efficiently transduce and amplify low-level ionic fluxes in biological systems into electronic output signals. In this work, we combine OECT-based drain current measurements with simultaneous measurement of more traditional impedance sensing using the gate current to produce complex impedance traces, which show low error at both low and high frequencies. We apply this technique in vitro to a model epithelial tissue layer and show that the data can be fit to an equivalent circuit model yielding trans-epithelial resistance and cell layer capacitance values in agreement with literature. Importantly, the combined measurement allows for low biases across the cell layer, while still maintaining good broadband signal.

  15. Tensegrity I. Cell structure and hierarchical systems biology

    Science.gov (United States)

    Ingber, Donald E.

    2003-01-01

    In 1993, a Commentary in this journal described how a simple mechanical model of cell structure based on tensegrity architecture can help to explain how cell shape, movement and cytoskeletal mechanics are controlled, as well as how cells sense and respond to mechanical forces (J. Cell Sci. 104, 613-627). The cellular tensegrity model can now be revisited and placed in context of new advances in our understanding of cell structure, biological networks and mechanoregulation that have been made over the past decade. Recent work provides strong evidence to support the use of tensegrity by cells, and mathematical formulations of the model predict many aspects of cell behavior. In addition, development of the tensegrity theory and its translation into mathematical terms are beginning to allow us to define the relationship between mechanics and biochemistry at the molecular level and to attack the larger problem of biological complexity. Part I of this two-part article covers the evidence for cellular tensegrity at the molecular level and describes how this building system may provide a structural basis for the hierarchical organization of living systems--from molecule to organism. Part II, which focuses on how these structural networks influence information processing networks, appears in the next issue.

  16. Spatial organization of mesenchymal stem cells in vitro--results from a new individual cell-based model with podia.

    Directory of Open Access Journals (Sweden)

    Martin Hoffmann

    Full Text Available Therapeutic application of mesenchymal stem cells (MSC requires their extensive in vitro expansion. MSC in culture typically grow to confluence within a few weeks. They show spindle-shaped fibroblastoid morphology and align to each other in characteristic spatial patterns at high cell density. We present an individual cell-based model (IBM that is able to quantitatively describe the spatio-temporal organization of MSC in culture. Our model substantially improves on previous models by explicitly representing cell podia and their dynamics. It employs podia-generated forces for cell movement and adjusts cell behavior in response to cell density. At the same time, it is simple enough to simulate thousands of cells with reasonable computational effort. Experimental sheep MSC cultures were monitored under standard conditions. Automated image analysis was used to determine the location and orientation of individual cells. Our simulations quantitatively reproduced the observed growth dynamics and cell-cell alignment assuming cell density-dependent proliferation, migration, and morphology. In addition to cell growth on plain substrates our model captured cell alignment on micro-structured surfaces. We propose a specific surface micro-structure that according to our simulations can substantially enlarge cell culture harvest. The 'tool box' of cell migratory behavior newly introduced in this study significantly enhances the bandwidth of IBM. Our approach is capable of accommodating individual cell behavior and collective cell dynamics of a variety of cell types and tissues in computational systems biology.

  17. Advanced photovoltaic power system technology for lunar base applications

    Science.gov (United States)

    Brinker, David J.; Flood, Dennis J.

    1992-01-01

    The development of an advanced photovoltaic power system that would have application for a manned lunar base is currently planned under the Surface Power element of Pathfinder. Significant mass savings over state-of-the-art photovoltaic/battery systems are possible with the use of advanced lightweight solar arrays coupled with regenerative fuel cell storage. The solar blanket, using either ultrathin GaAs or amorphous silicon solar cells, would be integrated with a reduced-g structure. Regenerative fuel cells with high-pressure gas storage in filament-wound tanks are planned for energy storage. An advanced PV/RFC power system is a leading candidate for a manned lunar base as it offers a tremendous weight advantage over state-of-the-art photovoltaic/battery systems and is comparable in mass to other advanced power generation technologies.

  18. Development of an Integrated Microfluidic Perfusion Cell Culture System for Real-Time Microscopic Observation of Biological Cells

    OpenAIRE

    Chih-Chin Oh-Yang; Min-Hsien Wu; Jr-Lung Lin; Shih-Siou Wang

    2011-01-01

    This study reports an integrated microfluidic perfusion cell culture system consisting of a microfluidic cell culture chip, and an indium tin oxide (ITO) glass-based microheater chip for micro-scale perfusion cell culture, and its real-time microscopic observation. The system features in maintaining both uniform, and stable chemical or thermal environments, and providing a backflow-free medium pumping, and a precise thermal control functions. In this work, the performance of the medium pumpin...

  19. Coded illumination for motion-blur free imaging of cells on cell-phone based imaging flow cytometer

    Science.gov (United States)

    Saxena, Manish; Gorthi, Sai Siva

    2014-10-01

    Cell-phone based imaging flow cytometry can be realized by flowing cells through the microfluidic devices, and capturing their images with an optically enhanced camera of the cell-phone. Throughput in flow cytometers is usually enhanced by increasing the flow rate of cells. However, maximum frame rate of camera system limits the achievable flow rate. Beyond this, the images become highly blurred due to motion-smear. We propose to address this issue with coded illumination, which enables recovery of high-fidelity images of cells far beyond their motion-blur limit. This paper presents simulation results of deblurring the synthetically generated cell/bead images under such coded illumination.

  20. Non-disruptive measurement system of cell viability in bioreactors

    Science.gov (United States)

    Rudek, F.; Nelsen, B. L.; Baselt, T.; Berger, T.; Wiele, M.; Prade, I.; Hartmann, P.

    2016-04-01

    Nutrient and oxygen transport, as well as the removal of metabolic waste are essential processes to support and maintain viable tissue. Current bioreactor technology used to grow tissue cultures in vitro has a fundamental limit to the thickness of tissues. Based on the low diffusion limit of oxygen a maximum tissue thickness of 200 μm is possible. The efficiency of those systems is currently under investigation. During the cultivation process of the artificial tissue in bioreactors, which lasts 28 days or longer, there are no possibilities to investigate the viability of cells. This work is designed to determine the influence of a non-disruptive cell viability measuring system on cellular activity. The measuring system uses a natural cellular marker produced during normal metabolic activity. Nicotinamide adenine dinucleotide (NADH) is a coenzyme naturally consumed and produced during cellular metabolic processes and has thoroughly been studied to determine the metabolic state of a cell. Measuring the fluorescence of NADH within the cell represents a non-disruptive marker for cell viability. Since the measurement process is optical in nature, NADH fluorescence also provides a pathway for sampling at different measurement depths within a given tissue sample. The measurement system we are using utilizes a special UV light source, to excite the NADH fluorescence state. However, the high energy potentially alters or harms the cells. To investigate the influence of the excitation signal, the cells were irradiated with a laser operating at a wavelength of 355 nm and examined for cytotoxic effects. The aim of this study was to develop a non-cytotoxic system that is applicable for large-scale operations during drug-tissue interaction testing.

  1. Phase Space Cell in Nonextensive Classical Systems

    CERN Document Server

    Quarati, F

    2003-01-01

    We calculate the phase space volume $Omega$ occupied by a nonextensive system of $N$ classical particles described by an equilibrium (or steady-state, or long-term stationary state of a nonequilibrium system) distribution function, which slightly deviates from Maxwell-Boltzmann (MB) distribution in the high energy tail. We explicitly require that the number of accessible microstates does not change respect to the extensive MB case. We also derive, within a classical scheme, an analytical expression of the elementary cell that can be seen as a macrocell, different from the third power of Planck constant. Thermodynamic quantities like entropy, chemical potential and free energy of a classical ideal gas, depending on elementary cell, are evaluated. Considering the fractional deviation from MB distribution we can deduce a physical meaning of the nonextensive parameter $q$ of the Tsallis nonextensive thermostatistics in terms of particle correlation functions (valid at least in the case, discussed in this work, of...

  2. Design of Propulsion System for a Fuel Cell Vehicle

    DEFF Research Database (Denmark)

    Schaltz, Erik; Andreasen, Søren Juhl; Rasmussen, Peter Omand

    2007-01-01

    This paper presents a design method of propulsion systems for fuel cell vehicles complying with the 42V PowerNet standard. The method is based on field measurements during several weeks. Several cases of combining energy storage devices to a common bus voltage are investigated, and the total mass......, volume, cost and efficiency of the propulsion system are compared. It is concluded that the number of energy storage devices and their connecting to the common bus have a significant affect of the mass, volume, cost and efficiency of the propulsion system....

  3. Systems Level Modeling of the Cell Cycle Using Budding Yeast

    Directory of Open Access Journals (Sweden)

    D.R. Kim

    2007-01-01

    Full Text Available Proteins involved in the regulation of the cell cycle are highly conserved across all eukaryotes, and so a relatively simple eukaryote such as yeast can provide insight into a variety of cell cycle perturbations including those that occur in human cancer. To date, the budding yeast Saccharomyces cerevisiae has provided the largest amount of experimental and modeling data on the progression of the cell cycle, making it a logical choice for in-depth studies of this process. Moreover, the advent of methods for collection of high-throughput genome, transcriptome, and proteome data has provided a means to collect and precisely quantify simultaneous cell cycle gene transcript and protein levels, permitting modeling of the cell cycle on the systems level. With the appropriate mathematical framework and suffi cient and accurate data on cell cycle components, it should be possible to create a model of the cell cycle that not only effectively describes its operation, but can also predict responses to perturbations such as variation in protein levels and responses to external stimuli including targeted inhibition by drugs. In this review, we summarize existing data on the yeast cell cycle, proteomics technologies for quantifying cell cycle proteins, and the mathematical frameworks that can integrate this data into representative and effective models. Systems level modeling of the cell cycle will require the integration of high-quality data with the appropriate mathematical framework, which can currently be attained through the combination of dynamic modeling based on proteomics data and using yeast as a model organism.

  4. Systemic adjuvant therapies in renal cell carcinoma

    OpenAIRE

    Sebastiano Buti; Melissa Bersanelli; Maddalena Donini; Andrea Ardizzoni

    2012-01-01

    Renal cell carcinoma (RCC) is one of the ten most frequent solid tumors worldwide. Recent innovations in the treatment of metastatic disease have led to new therapeutic approaches being investigated in the adjuvant setting. Observation is the only current standard of care after radical nephrectomy, although there is evidence of efficacy of adjuvant use of vaccine among all the strategies used. This article aims to collect published experiences with systemic adjuvant approaches in RCC and to d...

  5. Response Based Emergency Control System for Power System Transient Stability

    OpenAIRE

    Huaiyuan Wang; Baohui Zhang; Zhiguo Hao

    2015-01-01

    A transient stability control system for the electric power system composed of a prediction method and a control method is proposed based on trajectory information. This system, which is independent of system parameters and models, can detect the transient stability of the electric power system quickly and provide the control law when the system is unstable. Firstly, system instability is detected by the characteristic concave or convex shape of the trajectory. Secondly, the control method is...

  6. Regulated cell-to-cell variation in a cell-fate decision system.

    Science.gov (United States)

    Colman-Lerner, Alejandro; Gordon, Andrew; Serra, Eduard; Chin, Tina; Resnekov, Orna; Endy, Drew; Pesce, C Gustavo; Brent, Roger

    2005-09-29

    Here we studied the quantitative behaviour and cell-to-cell variability of a prototypical eukaryotic cell-fate decision system, the mating pheromone response pathway in yeast. We dissected and measured sources of variation in system output, analysing thousands of individual, genetically identical cells. Only a small proportion of total cell-to-cell variation is caused by random fluctuations in gene transcription and translation during the response ('expression noise'). Instead, variation is dominated by differences in the capacity of individual cells to transmit signals through the pathway ('pathway capacity') and to express proteins from genes ('expression capacity'). Cells with high expression capacity express proteins at a higher rate and increase in volume more rapidly. Our results identify two mechanisms that regulate cell-to-cell variation in pathway capacity. First, the MAP kinase Fus3 suppresses variation at high pheromone levels, while the MAP kinase Kss1 enhances variation at low pheromone levels. Second, pathway capacity and expression capacity are negatively correlated, suggesting a compensatory mechanism that allows cells to respond more precisely to pheromone in the presence of a large variation in expression capacity. PMID:16170311

  7. System for adding sulfur to a fuel cell stack system for improved fuel cell stability

    Science.gov (United States)

    Mukerjee, Subhasish; Haltiner, Jr., Karl J; Weissman, Jeffrey G

    2013-08-13

    A system for adding sulfur to a reformate stream feeding a fuel cell stack, having a sulfur source for providing sulfur to the reformate stream and a metering device in fluid connection with the sulfur source and the reformate stream. The metering device injects sulfur from the sulfur source to the reformate stream at a predetermined rate, thereby providing a conditioned reformate stream to the fuel cell stack. The system provides a conditioned reformate stream having a predetermined sulfur concentration that gives an acceptable balance of minimal drop in initial power with the desired maximum stability of operation over prolonged periods for the fuel cell stack.

  8. Multifunctional non-viral delivery systems based on conjugated polymers.

    Science.gov (United States)

    Yang, Gaomai; Lv, Fengting; Wang, Bing; Liu, Libing; Yang, Qiong; Wang, Shu

    2012-12-01

    Multifunctional nanomaterials with simultaneous therapeutic and imaging functions explore new strategies for the treatment of various diseases. Conjugated polymers (CPs) are considered as novel candidates to serve as multifunctional delivery systems due to their high fluorescence quantum yield, good photostability, and low cytotoxicity. Highly sensitive sensing and imaging properties of CPs are well reviewed, while the applications of CPs as delivery systems are rarely covered. This feature article mainly focuses on CP-based multifunctional non-viral delivery systems for drug, protein, gene, and cell delivery. Promising directions for the further development of CP-based delivery systems are also discussed.

  9. Area Logistics System Based on System Dynamics Model

    Institute of Scientific and Technical Information of China (English)

    GUI Shouping; ZHU Qiang; LU Lifang

    2005-01-01

    At present, there are few effective ways to analyze area logistics systems. This paper uses system dynamics to analyze the area logistics system and establishes a system dynamics model for the area logistics system based on the characteristics of the area logistics system and system dynamics. Numerical simulations with the system dynamic model were used to analyze a logistic system. Analysis of the Guangzhou economy shows that the model can reflect the actual state of the system objectively and can be used to make policy and harmonize environment.

  10. Microprocessor based systems for the higher technician

    CERN Document Server

    Vears, RE

    2013-01-01

    Microprocessor Based Systems for the Higher Technician provides coverage of the BTEC level 4 unit in Microprocessor Based Systems (syllabus U80/674). This book is composed of 10 chapters and concentrates on the development of 8-bit microcontrollers specifically constructed around the Z80 microprocessor. The design cycle for the development of such a microprocessor based system and the use of a disk-based development system (MDS) as an aid to design are both described in detail. The book deals with the Control Program Monitor (CP/M) operating system and gives background information on file hand

  11. Expert system for web based collaborative CAE

    Science.gov (United States)

    Hou, Liang; Lin, Zusheng

    2006-11-01

    An expert system for web based collaborative CAE was developed based on knowledge engineering, relational database and commercial FEA (Finite element analysis) software. The architecture of the system was illustrated. In this system, the experts' experiences, theories and typical examples and other related knowledge, which will be used in the stage of pre-process in FEA, were categorized into analysis process and object knowledge. Then, the integrated knowledge model based on object-oriented method and rule based method was described. The integrated reasoning process based on CBR (case based reasoning) and rule based reasoning was presented. Finally, the analysis process of this expert system in web based CAE application was illustrated, and an analysis example of a machine tool's column was illustrated to prove the validity of the system.

  12. Solar cells on the base of organic semiconductors

    International Nuclear Information System (INIS)

    The parameters of organic solar cells on the base of different organic semiconductors as poly epoxypropyl carbazole, copper phthalocyanine and bordeaux perylene are considered. Moreover the properties of solar cells on the base of n-GaAs and copper phthalocyanine heterostructure are described. The new technologies in the field of organic solar cells as bulk heterostructure solar cells are discussed. (author)

  13. Cell-Based Therapy for Silicosis.

    Science.gov (United States)

    Lopes-Pacheco, Miquéias; Bandeira, Elga; Morales, Marcelo M

    2016-01-01

    Silicosis is the most common pneumoconiosis globally, with higher prevalence and incidence in developing countries. To date, there is no effective treatment to halt or reverse the disease progression caused by silica-induced lung injury. Significant advances have to be made in order to reduce morbidity and mortality related to silicosis. In this review, we have highlighted the main mechanisms of action that cause lung damage by silica particles and summarized the data concerning the therapeutic promise of cell-based therapy for silicosis. PMID:27066079

  14. Cell-Based Therapy for Silicosis

    Directory of Open Access Journals (Sweden)

    Miquéias Lopes-Pacheco

    2016-01-01

    Full Text Available Silicosis is the most common pneumoconiosis globally, with higher prevalence and incidence in developing countries. To date, there is no effective treatment to halt or reverse the disease progression caused by silica-induced lung injury. Significant advances have to be made in order to reduce morbidity and mortality related to silicosis. In this review, we have highlighted the main mechanisms of action that cause lung damage by silica particles and summarized the data concerning the therapeutic promise of cell-based therapy for silicosis.

  15. Silicon Based Direct Methanol Fuel Cells

    DEFF Research Database (Denmark)

    Larsen, Jackie Vincent

    collector electrodes. This design is based on catalytic in situ growth of carbon nanotubes and atomic layer deposition of active catalyst particles. The additional two fuel cell designs utilize a porous silicon structure as the mechanical support, using respectively a spray coated catalyst and atomic layer...... deposition for. This method of integration was investigated as a high internal volume support structure with potential for rapid batch fabrication. In characterization of the devices the work presents the development of an electrochemical impedance spectroscopy measurement setup capable of determining...

  16. Plc Based Scrap Management System

    Directory of Open Access Journals (Sweden)

    Nidhi Mishra

    2014-03-01

    Full Text Available In this paper we have implemented an automated scrap management system for Maintenance Department of Bharat Forge Ltd. Hadapsar, Pune. Bharat Forge is a well known industry for manufacturing of Crank Shaft and various kinds of axels. To manage the scrap & wastage during mass production is a tedious and time consuming job. Scrap Management System is used for storing the scrap & garbage. This Scrap Management System had several problem like huge manpower requirement, time due to which there may be chances of misoperation due to unawareness of handling the system. When any fault is generated due to locking or mechanical operating problem of limit switches, the whole operation can be halt. These flaws lead to increasing concern regarding safety operations and constant maintenance. The conventional system which is in use was developed with a relay logic to control all its operations. But due to bulkiness of the relay logic and number of wiring there are lot of problems during maintenance of the system. This leads to develop some efficient system which find a solution to the painstaking maintenance problems of relay logic, ease of handling, reduction of manpower, & nullify the storing problem of scrap. This can be satisfactorily achieved by replacing the old relay logic by a newly designed PLC system by us.

  17. Translation in cell-free systems

    International Nuclear Information System (INIS)

    The simplest, unambiguous identification of a particular mRNA is the identification of its protein product. This can be established by translation of the mRNA of interest in a cell-free protein-synthesizing system. Messenger RNA protein product identification is important in the isolation of a particular mRNA species for cDNA cloning and in the identification of positive cDNA clones. The two high-activity translation systems in common use are those prepared from rabbit reticulocytes and from wheat germ. Both systems are easy to prepare, and both are available commercially. Each has advantages and disadvantages over the other and a choice between the two will depend on the type of mRNAs to be translated, the prejudices of experience, and availability. The main disadvantage of the reticulocyte system is that it requires removal of endogenous mRNA. However, this is a relatively simple procedure. The wheat germ system does not require removal of endogenous mRNA and may translate weakly initiating mRNAs more efficiently. However, ionic optima for translation in the wheat germ system are more sensitive to the nature and concentration of mRNA and may need to be determined for each template. The biggest problem with the use of the wheat germ system is its tendency to produce incomplete translation products due to premature termination

  18. System design of a large fuel cell hybrid locomotive

    Science.gov (United States)

    Miller, A. R.; Hess, K. S.; Barnes, D. L.; Erickson, T. L.

    Fuel cell power for locomotives combines the environmental benefits of a catenary-electric locomotive with the higher overall energy efficiency and lower infrastructure costs of a diesel-electric. A North American consortium, a public-private partnership, is developing a prototype hydrogen-fueled fuel cell-battery hybrid switcher locomotive for urban and military-base rail applications. Switcher locomotives are used in rail yards for assembling and disassembling trains and moving trains from one point to another. At 127 tonnes (280,000 lb), continuous power of 250 kW from its (proton exchange membrane) PEM fuel cell prime mover, and transient power well in excess of 1 MW, the hybrid locomotive will be the heaviest and most powerful fuel cell land vehicle yet. This fast-paced project calls for completion of the vehicle itself near the end of 2007. Several technical challenges not found in the development of smaller vehicles arise when designing and developing such a large fuel cell vehicle. Weight, center of gravity, packaging, and safety were design factors leading to, among other features, the roof location of the lightweight 350 bar compressed hydrogen storage system. Harsh operating conditions, especially shock loads during coupling to railcars, require component mounting systems capable of absorbing high energy. Vehicle scale-up by increasing mass, density, or power presents new challenges primarily related to issues of system layout, hydrogen storage, heat transfer, and shock loads.

  19. System design of a large fuel cell hybrid locomotive

    Energy Technology Data Exchange (ETDEWEB)

    Miller, A.R.; Hess, K.S.; Barnes, D.L.; Erickson, T.L. [Vehicle Projects LLC, 621 17th Street, Suite 2131, Denver, CO 80293 (United States)

    2007-11-15

    Fuel cell power for locomotives combines the environmental benefits of a catenary-electric locomotive with the higher overall energy efficiency and lower infrastructure costs of a diesel-electric. A North American consortium, a public-private partnership, is developing a prototype hydrogen-fueled fuel cell-battery hybrid switcher locomotive for urban and military-base rail applications. Switcher locomotives are used in rail yards for assembling and disassembling trains and moving trains from one point to another. At 127 tonnes (280,000 lb), continuous power of 250 kW from its (proton exchange membrane) PEM fuel cell prime mover, and transient power well in excess of 1 MW, the hybrid locomotive will be the heaviest and most powerful fuel cell land vehicle yet. This fast-paced project calls for completion of the vehicle itself near the end of 2007. Several technical challenges not found in the development of smaller vehicles arise when designing and developing such a large fuel cell vehicle. Weight, center of gravity, packaging, and safety were design factors leading to, among other features, the roof location of the lightweight 350 bar compressed hydrogen storage system. Harsh operating conditions, especially shock loads during coupling to railcars, require component mounting systems capable of absorbing high energy. Vehicle scale-up by increasing mass, density, or power presents new challenges primarily related to issues of system layout, hydrogen storage, heat transfer, and shock loads. (author)

  20. Reprogramming of mouse amniotic fluid cells using a PiggyBac transposon system

    Directory of Open Access Journals (Sweden)

    E. Bertin

    2015-11-01

    Full Text Available Induced pluripotent stem (iPS cells are generated from mouse and human somatic cells by forced expression of defined transcription factors using different methods. Amniotic fluid (AF cells are easy to obtain from routinely scheduled procedures for prenatal diagnosis and iPS cells have been generated from human AF. Here, we generated iPS cells from mouse AF cells, using a non-viral-based approach constituted by the PiggyBac (PB transposon system. All iPS cell lines obtained exhibited characteristics of pluripotent cells, including the ability to differentiate toward derivatives of all three germ layers in vitro and in vivo.

  1. Systems, methods and computer-readable media for modeling cell performance fade of rechargeable electrochemical devices

    Science.gov (United States)

    Gering, Kevin L

    2013-08-27

    A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware periodically samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics of the electrochemical cell. The computing system also develops a mechanistic level model of the electrochemical cell to determine performance fade characteristics of the electrochemical cell and analyzing the mechanistic level model to estimate performance fade characteristics over aging of a similar electrochemical cell. The mechanistic level model uses first constant-current pulses applied to the electrochemical cell at a first aging period and at three or more current values bracketing a first exchange current density. The mechanistic level model also is based on second constant-current pulses applied to the electrochemical cell at a second aging period and at three or more current values bracketing the second exchange current density.

  2. Electric vehicles and renewable energy in the transport sector - energy system consequences. Main focus: Battery electric vehicles and hydrogen based fuel cell vehicles

    OpenAIRE

    Nielsen, L.H.; Jørgensen K., null

    2000-01-01

    The aim of the project is to analyse energy, environmental and economic aspects of integrating electric vehicles in the future Danish energy system. Consequences of large-scale utilisation of electric vehicles are analysed. The aim is furthermore toillustrate the potential synergistic interplay between the utilisation of electric vehicles and large-scale utilisation of fluctuating renewable energy resources, such as wind power. Economic aspects for electric vehicles interacting with a liberal...

  3. Advanced ECU Software Development Method for Fuel Cell Systems

    Institute of Scientific and Technical Information of China (English)

    TIAN Shuo; LIU Yuan; XIA Wenchuan; LI Jianqiu; YANG Minggao

    2005-01-01

    The electronic control unit (ECU) in electrical powered hybrid and fuel cell vehicles is exceedingly complex. Rapid prototyping control is used to reduce development time and eliminate errors during software development. This paper describes a high-efficiency development method and a flexible tool chain suitable for various applications in automotive engineering. The control algorithm can be deployed directly from a Matlab/Simulink/Stateflow environment into the ECU hardware together with an OSEK real-time operating system (RTOS). The system has been successfully used to develop a 20-kW fuel cell system ECU based on a Motorola PowerPC 555 (MPC555) microcontroller. The total software development time is greatly reduced and the code quality and reliability are greatly enhanced.

  4. A Novel Cell-Based Hybrid Acoustic Wave Biosensor with Impedimetric Sensing Capabilities

    OpenAIRE

    Ioana Voiculescu; Anis Nurashikin Nordin; Fang Li; Fei Liu

    2013-01-01

    A novel multiparametric biosensor system based on living cells will be presented. The biosensor system includes two biosensing techniques on a single device: resonant frequency measurements and electric cell-substrate impedance sensing (ECIS). The multiparametric sensor system is based on the innovative use of the upper electrode of a quartz crystal microbalance (QCM) resonator as working electrode for the ECIS technique. The QCM acoustic wave sensor consists of a thin AT-cut quartz substrate...

  5. Reliability-Based Optimization of Series Systems of Parallel Systems

    DEFF Research Database (Denmark)

    Enevoldsen, I.; Sørensen, John Dalsgaard

    Reliability-based design of structural systems is considered. Especially systems where the reliability model is a series system of parallel systems are analysed. A sensitivity analysis for this class of problems is presented. Direct and sequential optimization procedures to solve the optimization...... problems are described. Numerical tests indicate that a sequential technique called the bounds iteration method (BIM) is particularly fast and stable....

  6. Laser-based agriculture system

    KAUST Repository

    Ooi, Boon S.

    2016-03-31

    A system and method are provided for indoor agriculture using at least one growth chamber illuminated by laser light. In an example embodiment of the agriculture system, a growth chamber is provided having one or more walls defining an interior portion of the growth chamber. The agriculture system may include a removable tray disposed within the interior portion of the growth chamber. The agriculture system also includes a light source, which may be disposed outside the growth chamber. The one or more walls may include at least one aperture. The light source is configured to illuminate at least a part of the interior portion of the growth chamber. In embodiments in which the light source is disposed outside the growth chamber, the light source is configured to transmit the laser light to the interior portion of the growth chamber via the at least one aperture.

  7. Liquid monobenzoxazine based resin system

    Energy Technology Data Exchange (ETDEWEB)

    Tietze, Roger; Nguyen, Yen-Loan; Bryant, Mark

    2014-10-07

    The present invention provides a liquid resin system including a liquid monobenzoxazine monomer and a non-glycidyl epoxy compound, wherein the weight ratio of the monobenzoxazine monomer to the non-glycidyl epoxy compound is in a range of about 25:75 to about 60:40. The liquid resin system exhibits a low viscosity and exceptional stability over an extended period of time making its use in a variety of composite manufacturing methods highly advantageous.

  8. 基于单神经元-PID的液压变桨距控制系统的设计%The Design of Hydraulic Pitch-control System Based on Single Neuron Cell PID

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    An intelligent PID control calculation is developed using single neuron,combining the advantages such as adaptability, self-learning, simple structure, short weight learning time, small computational amount and strong ro-bustness. Through the experimental study, it indicated that the hydraulic pitch-control system based on single neuron cell PID can better meet the requirements of nonlinear dynamics of the system and parameter time-variation than the classical PID control system.%  提出的单神经元-PID液压变桨距控制方法,结合了单神经元自适应性,自学习,结构简单,权值学习时间短,计算量小,鲁棒性强等优点,并通过实验,对该控制方法进行了验证,证明了其相比常规PID控制的优越性,能更好地满足风力变桨距系统的非线性,参数时变性的要求。

  9. Consent Based Verification System (CBSV)

    Data.gov (United States)

    Social Security Administration — CBSV is a fee-based service offered by SSA's Business Services Online (BSO). It is used by private companies to verify the SSNs of their customers and clients that...

  10. Fiber-Based Ultraviolet Laser System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this program is to develop a compact and efficient ultraviolet laser system for use in space-based uv-Raman instruments. The basis for this system...

  11. Rapid detection of microbial cell abundance in aquatic systems.

    Science.gov (United States)

    Rocha, Andrea M; Yuan, Quan; Close, Dan M; O'Dell, Kaela B; Fortney, Julian L; Wu, Jayne; Hazen, Terry C

    2016-11-15

    The detection and quantification of naturally occurring microbial cellular densities is an essential component of environmental systems monitoring. While there are a number of commonly utilized approaches for monitoring microbial abundance, capacitance-based biosensors represent a promising approach because of their low-cost and label-free detection of microbial cells, but are not as well characterized as more traditional methods. Here, we investigate the applicability of enhanced alternating current electrokinetics (ACEK) capacitive sensing as a new application for rapidly detecting and quantifying microbial cellular densities in cultured and environmentally sourced aquatic samples. ACEK capacitive sensor performance was evaluated using two distinct and dynamic systems - the Great Australian Bight and groundwater from the Oak Ridge Reservation in Oak Ridge, TN. Results demonstrate that ACEK capacitance-based sensing can accurately determine microbial cell counts throughout cellular concentrations typically encountered in naturally occurring microbial communities (10(3)-10(6) cells/mL). A linear relationship was observed between cellular density and capacitance change correlations, allowing a simple linear curve fitting equation to be used for determining microbial abundances in unknown samples. This work provides a foundation for understanding the limits of capacitance-based sensing in natural environmental samples and supports future efforts focusing on evaluating the robustness ACEK capacitance-based within aquatic environments. PMID:27315516

  12. Fuel processor for fuel cell power system

    Science.gov (United States)

    Vanderborgh, Nicholas E.; Springer, Thomas E.; Huff, James R.

    1987-01-01

    A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

  13. Laser-based patterning for transfected cell microarrays

    Energy Technology Data Exchange (ETDEWEB)

    Hook, Andrew L; Creasey, Rhiannon; Voelcker, Nicolas H [Flinders University, GPO Box 2100, Bedford Park, SA 5042 (Australia); Hayes, Jason P [MiniFAB, 1 Dalmore Drive, Caribbean Park, Scoresby VIC 3179 (Australia); Thissen, Helmut, E-mail: Nico.Voelcker@flinders.edu.a [CSIRO Molecular and Health Technologies, Bayview Avenue, Clayton VIC 3168 (Australia)

    2009-12-15

    The spatial control over biomolecule- and cell-surface interactions is of great interest to a broad range of biomedical applications, including sensors, implantable devices and cell microarrays. Microarrays in particular require precise spatial control and the formation of patterns with microscale features. Here, we have developed an approach specifically designed for transfected cell microarray (TCM) applications that allows microscale spatial control over the location of both DNA and cells on highly doped p-type silicon substrates. This was achieved by surface modification, involving plasma polymerization of allylamine, grafting of poly(ethylene glycol) and subsequent excimer laser ablation. DNA could be delivered in a spatially defined manner using ink-jet printing. In addition, electroporation was investigated as an approach to transfect attached cells with adsorbed DNA and good transfection efficiencies of approximately 20% were observed. The ability of the microstructured surfaces to spatially direct both DNA adsorption and cell attachment was demonstrated in a functional TCM, making this system an exciting platform for chip-based functional genomics.

  14. Performance benchmarking of four cell-free protein expression systems.

    Science.gov (United States)

    Gagoski, Dejan; Polinkovsky, Mark E; Mureev, Sergey; Kunert, Anne; Johnston, Wayne; Gambin, Yann; Alexandrov, Kirill

    2016-02-01

    Over the last half century, a range of cell-free protein expression systems based on pro- and eukaryotic organisms have been developed and have found a range of applications, from structural biology to directed protein evolution. While it is generally accepted that significant differences in performance among systems exist, there is a paucity of systematic experimental studies supporting this notion. Here, we took advantage of the species-independent translation initiation sequence to express and characterize 87 N-terminally GFP-tagged human cytosolic proteins of different sizes in E. coli, wheat germ (WGE), HeLa, and Leishmania-based (LTE) cell-free systems. Using a combination of single-molecule fluorescence spectroscopy, SDS-PAGE, and Western blot analysis, we assessed the expression yields, the fraction of full-length translation product, and aggregation propensity for each of these systems. Our results demonstrate that the E. coli system has the highest expression yields. However, we observe that high expression levels are accompanied by production of truncated species-particularly pronounced in the case of proteins larger than 70 kDa. Furthermore, proteins produced in the E. coli system display high aggregation propensity, with only 10% of tested proteins being produced in predominantly monodispersed form. The WGE system was the most productive among eukaryotic systems tested. Finally, HeLa and LTE show comparable protein yields that are considerably lower than the ones achieved in the E. coli and WGE systems. The protein products produced in the HeLa system display slightly higher integrity, whereas the LTE-produced proteins have the lowest aggregation propensity among the systems analyzed. The high quality of HeLa- and LTE-produced proteins enable their analysis without purification and make them suitable for analysis of multi-domain eukaryotic proteins.

  15. Optimization of Fuel Cell System Operating Conditions for Fuel Cell Vehicles

    OpenAIRE

    Zhao, Hengbing; Burke, Andy

    2008-01-01

    Proton Exchange Membrane fuel cell (PEMFC) technology for use in fuel cell vehicles and other applications has been intensively developed in recent decades. Besides the fuel cell stack, air and fuel control and thermal and water management are major challenges in the development of the fuel cell for vehicle applications. The air supply system can have a major impact on overall system efficiency. In this paper a fuel cell system model for optimizing system operating conditions was developed wh...

  16. Pervasive Computing Based Intelligent Energy Conservation System

    OpenAIRE

    Dr. A.Kanagaraj; Ms S.Sharmila

    2015-01-01

    Most of the HVAC system in home is running based on static control algorithm; based on fixed work schedules. In that old system energy became waste when home contains low or no people occupancy. In this paper we presented new dynamic approach of HVAC system control, by combined with pervasive computing. Pervasive computing can be defined as availability of centralized system and information anywhere and anytime. We achieved our target by using occupancy sensors for collecting home status. ...

  17. SPIRE Data-Base Management System

    Science.gov (United States)

    Fuechsel, C. F.

    1984-01-01

    Spacelab Payload Integration and Rocket Experiment (SPIRE) data-base management system (DBMS) based on relational model of data bases. Data bases typically used for engineering and mission analysis tasks and, unlike most commercially available systems, allow data items and data structures stored in forms suitable for direct analytical computation. SPIRE DBMS designed to support data requests from interactive users as well as applications programs.

  18. Self-assembled hybrid materials based on conjugated polymers and semiconductors nano-crystals for plastic solar cells; Architectures hybrides auto-assemblees a base de systemes polyconjugues et de nanocristaux de semi-conducteurs pour le photovoltaique plastique

    Energy Technology Data Exchange (ETDEWEB)

    Girolamo, J. de

    2007-11-15

    This work is devoted to the elaboration of self-assembled hybrid materials based on poly(3- hexyl-thiophene) and CdSe nano-crystals for photovoltaic applications. For that, complementary molecular recognition units were introduced as side chain groups on the polymer and at the nano-crystals' surface. Diamino-pyrimidine groups were introduced by post-functionalization of a precursor copolymer, namely poly(3-hexyl-thiophene-co-3- bromo-hexyl-thiophene) whereas thymine groups were introduced at the nano-crystals' surface by a ligand exchange reaction with 1-(6-mercapto-hexyl)thymine. However, due to their different solubility, the mixing of the two components by solution processes is difficult. A 'one-pot' procedure was developed, but this method led to insoluble aggregates without control of the hybrid composition. To overcome the solubility problem, the layer-by-layer method was used to prepare the films. This method allows a precise control of the deposition process. Experimental parameters were tested in order to evaluate their impact on the resulting film. The films morphology was investigated by microscopy and X-Ray diffraction techniques. These analyses reveal an interpenetrated structure of nano-crystals within the polymer matrix rather than a multilayered structure. Electrochemical and spectro electrochemical studies were performed on the hybrid material deposited by the LBL process. Finally the materials were tested in a solar cell configuration and the I=f(V) curves reveals a clear photovoltaic behaviour. (author)

  19. LINUX BASED CLOUD OPERATING SYSTEM

    Directory of Open Access Journals (Sweden)

    Ravindra Gupta

    2012-02-01

    Full Text Available Cloud computing is a type of computing in which dynamically scalable and virtualized resources are provided as a service. Users need not have knowledge of, expertise in, or control over the technology infrastructure in the cloud that supports them. Furthermore, cloud computing employs a model for enabling available, convenient and on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, services that can be rapidly provisioned and released with minimal management effort or service provider interaction. The services mainly operating systems running on a single virtualized computing environment, middleware layers that attempt to combine physical and virtualized resources from multiple operating systems, and specialized application engines. In this paper, we discuss about the virtual distributed operating system, Cloud Operating System, to provide maximum features of cloud computing. The Cloud Operating System will work on the principle laid out by LINUX. The Cloud OS aims to provide simple programming abstractions to available cloud resources, strong isolation techniques between Cloud processes, and strong integration with network resources.

  20. Pervasive Computing Based Intelligent Energy Conservation System

    Directory of Open Access Journals (Sweden)

    Dr. A.Kanagaraj

    2015-11-01

    Full Text Available Most of the HVAC system in home is running based on static control algorithm; based on fixed work schedules. In that old system energy became waste when home contains low or no people occupancy. In this paper we presented new dynamic approach of HVAC system control, by combined with pervasive computing. Pervasive computing can be defined as availability of centralized system and information anywhere and anytime. We achieved our target by using occupancy sensors for collecting home status. Initially our occupancy sensors collect human presence and current HVAC status details and stored in centralized system. Then based on our user defined threshold value the centralized system maintains the building's heating, cooling and air quality conditions by controlling HVAC devices. I.e. this system turned off HVAC systems when a home is unoccupied, or put the system into an energy saving sleep mode when persons are asleep.

  1. All-polymer microfluidic systems for droplet based sample analysis

    DEFF Research Database (Denmark)

    Poulsen, Carl Esben

    In this PhD project, I pursued to develop an all-polymer injection moulded microfluidic platform with integrated droplet based single cell interrogation. To allow for a proper ”one device - one experiment” methodology and to ensure a high relevancy to non-academic settings, the systems presented ...

  2. Web based facial recognition system

    OpenAIRE

    Pujol Aparicio, Adrià

    2016-01-01

    As the online academic offer increases, the rise of new challenges comes along. One of the problems that come with the territory of online exams is the new ways of cheating the tests. That is the reason why the need of a system that handles the verification of the individuals that are taking part in the examination process is needed, that way the absence of a fraudulent use of the system is being ensured. The goal of this project is to help with the legitimacy of the verification process of t...

  3. Troubleshooting on microprocessor based systems

    CERN Document Server

    Williams, G B

    1984-01-01

    The structure of a computing system presents unique problems when it fails to operate correctly and requires testing. This concise, yet comprehensive book describes the major test methods in current use, and their development from basic principles. Examines the sequence of tests which, built on each other, provide a suitable vehicle for testing digital systems, and the various types of testing equipment that should be applied for specific tests. An excellent introduction for those entering this increasingly complex world, the text will provide the reader with a firm basis on which to judge

  4. Analysis of Syetem Reliability in Manufacturing Cell Based on Triangular Fuzzy Number

    Institute of Scientific and Technical Information of China (English)

    ZHANG Caibo; HAN Botang; SUN Changsen; XU Chunjie

    2006-01-01

    Due to lacking of test-data and field-data in reliability research during the design stage of manufacturing cell system. The degree of manufacturing cell system reliability research is increased. In order to deal with the deficient data and the uncertainty occurred from analysis and judgment, the paper discussed a method for studying reliability of manufacturing cell system through the analysis of fuzzy fault tree, which was based on triangular fuzzy number. At last, calculation case indicated that it would have great significance for ascertaining reliability index, maintenance and establishing keeping strategy towards manufacturing cell system.

  5. Reflectable bases for affine reflection systems

    CERN Document Server

    Azam, Saeid; Yousofzadeh, Malihe

    2011-01-01

    The notion of a "root base" together with its geometry plays a crucial role in the theory of finite and affine Lie theory. However, it is known that such a notion does not exist for the recent generalizations of finite and affine root systems such as extended affine root systems and affine reflection systems. As an alternative, we introduce the notion of a "reflectable base", a minimal subset $\\Pi$ of roots such that the non-isotropic part of the root system can be recovered by reflecting roots of $\\Pi$ relative to the hyperplanes determined by $\\Pi$. We give a full characterization of reflectable bases for tame irreducible affine reflection systems of reduced types, excluding types $E_{6,7,8}$. As a byproduct of our results, we show that if the root system under consideration is locally finite then any reflectable base is an integral base.

  6. 槽式聚光系统聚光硅电池阵列特性实验研究%Characteristic Investigation of Concentration Silicon Solar Cell Arrays Based on the Trough Concentrating System

    Institute of Scientific and Technical Information of China (English)

    许玲; 李明; 李国良; 黄波; 魏生贤

    2011-01-01

    The performance tests of two types of domestic concentration silicon cell arrays with parallel and inverted square grid-line distribution based on the trough concentrating photovoltaic/thermal system have been carried out.Experimental results indicate that photoelectric efficiencies of the two selected concentration silicon solar cell arrays reach 11.42% and 13.89%.The maximum output power amplifies 16.06 times and 19.33 times respectively with energy flux concentration ratio 20 times.The temperature coefficients of Pm, FF and 77 of the two cell arrays are -0.047 W/K、 -0.45%/K、 -0.035%/K and -0.029 W/K、 -0.176%/K、 -0.105%/K respectively.All those works provide reference for choosing concentrating solar cells and optimizing performance of trough concentrating photovoltaic/ thermal system.%利用所设计的槽式聚光热电联供系统,对栅线平行分布和反方形分布的两种聚光硅太阳电池阵列进行了性能测试研究.结果表明,在能流聚光比为20倍的槽式聚光器下,两种电池阵列的光电效率分别为11.42%和13.89%,最大输出功率分别比聚光前放大16.06倍和19.33倍.两种电池阵列Pm、FF和η的温度系数分别为:-0.047 W/K、-0.45%/K、-0.035%/K;-0.029 W/K、-0.176%/K、-0.105%/K.研究结果为中低倍聚光系统聚光电池的选择和槽式聚光热电联供系统性能的优化提供参考.

  7. Response Based Emergency Control System for Power System Transient Stability

    Directory of Open Access Journals (Sweden)

    Huaiyuan Wang

    2015-11-01

    Full Text Available A transient stability control system for the electric power system composed of a prediction method and a control method is proposed based on trajectory information. This system, which is independent of system parameters and models, can detect the transient stability of the electric power system quickly and provide the control law when the system is unstable. Firstly, system instability is detected by the characteristic concave or convex shape of the trajectory. Secondly, the control method is proposed based on the analysis of the slope of the state plane trajectory when the power system is unstable. Two control objectives are provided according to the methods of acquiring the far end point: one is the minimal cost to restore the system to a stable state; the other one is the minimal cost to limit the maximum swing angle. The simulation indicates that the mentioned transient stability control system is efficient.

  8. 热处理对不同溶剂制备的共混体系太阳电池性能影响%Annealing treatment effects on the performances of solar cells based on different solvent blend systems

    Institute of Scientific and Technical Information of China (English)

    於黄忠; 周晓明; 邓俊裕

    2011-01-01

    The solar cells based on different solvent blends of poly(3-hexylthiophene) (P3HT) and [6,6 ]-phenyl C61-butyric acid methyl ester (PCBM) as acceptors are fabricated. Annealing treatment effects on the performances of solar cells based on different solvent blend systems are analyzed by UV-vis absorption spectroscopy and photoluminescence (PL) spectroscopy. The results show that high boiling point solvent leads to an enhanced P3HT ordering in the P3HT:PCBM blend system, and causes an increased incident light absorption and PL spectrum, which contributes to the enhancement of device performance. After 130 ~C thermal annealing, The UV-Vis absorption, PL spectrum and the performance of the device are further enhanced. The performance of the device prepared with low boiling point chloroform solvent increases obviously after thermal annealing. The solar cell prepared with chlorobenzene solvent after 130 ~C thermal annealing achieves an open circuit voltage(Voo) of O. 57 V, short circuit current density (Iso) of 8.74 mA/cm2 , fill factor (FF) of 59.2% and power conversion efficiency (PCE) of 2.95% under 100 mW/cm2 air-mass 1.5 solar simulator illumination.%本文以poly(3-hexylthiophene)(P3HT)为电子给体材料,[6,6]-phenyl C61-butyric acid methyl ester(PCBM)为电子受体材料,制备出不同溶剂形成的共混体系太阳电池.从薄膜的紫外一可见吸收光谱(uV—vis)、光致发光谱(PL)、原子力表面图形(AFM)等方面,分析了热处理对不同溶剂制备的共混体系太阳电池性能的影响.结果表明较高沸点的溶剂有利于P3HT:PCBM共混体系中P3HT的有序化排列,薄膜的紫外一可见吸收和光致发光增强,太阳电池的能量转

  9. Stem Cell-Based Therapies for Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Lei Hao

    2014-01-01

    Full Text Available In recent years, stem cell-based approaches have attracted more attention from scientists and clinicians due to their possible therapeutical effect on stroke. Animal studies have demonstrated that the beneficial effects of stem cells including embryonic stem cells (ESCs, inducible pluripotent stem cells (iPSCs, neural stem cells (NSCs, and mesenchymal stem cell (MSCs might be due to cell replacement, neuroprotection, endogenous neurogenesis, angiogenesis, and modulation on inflammation and immune response. Although several clinical studies have shown the high efficiency and safety of stem cell in stroke management, mainly MSCs, some issues regarding to cell homing, survival, tracking, safety, and optimal cell transplantation protocol, such as cell dose and time window, should be addressed. Undoubtably, stem cell-based gene therapy represents a novel potential therapeutic strategy for stroke in future.

  10. Design and implementation of cell resistance measurement system based on square wave constant current source%基于方波恒流源细胞电阻测量系统的设计实现

    Institute of Scientific and Technical Information of China (English)

    郝丽俊; 单纯玉; 白宝丹

    2015-01-01

    A cell resistance measurement system based on a constant current source is designed .In the system ,AC square w ave micro‐current signal is first being applied to the cells or the cell mass ,and then an output square‐w ave volt‐age proportional to the measuring cell resistance is obtained according to Ohm's law .Finally digital display values can be attained after rectification and A/D conversion .The application of constant current source can effectively improve meas‐urement accuracy by eliminating the effect on the measuring results of the cell membrane potential and measuring elec‐trode electrolysis .And also ,as using square wave ,the DC influence can be easily filtered by the system with simple cir‐cuit .Finally ,using saline to simulate experimental cell fluid ,the experiment shows that with the increasing distance of test probes ,the measured resistance is increased in direct proportion and the results have little effect on polarization and effective .In addition , results demonstrate that the mean square error is less than 6% in the measurement range 0 -1 000 Ω and it can basically meet to the needs of isolated assisted detection in clinically .%设计实现了一个细胞电阻测量系统。该系统基于方波恒流源电路,将交流方波微电流信号施加在被测细胞或细胞群上,根据欧姆定律,输出与被测细胞电阻成正比的交流方波电压,再经滤波、整流、A/D转换后获得电阻数字显示值。系统中恒流源的应用有效消除了测量电极电解作用及细胞膜电位对测量结果的影响,方波电压的产生则便于进一步滤除直流干扰成分,提高测量准确度。利用生理盐水模拟细胞液进行实验,可以观察到随着测试表笔距离的加大,测量电阻也在做正比例增加,结果受表笔电极化影响很小,且在有效测量范围0~1000Ω内,测量均方误差小于6%,能够基本满足临床上离体辅助检测的需求。

  11. Improved generalized cell mapping for global analysis of dynamical systems

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Three main parts of generalized cell mapping are improved for global analysis. A simple method, which is not based on the theory of digraphs, is presented to locate complete self-cycling sets that corre- spond to attractors and unstable invariant sets involving saddle, unstable periodic orbit and chaotic saddle. Refinement for complete self-cycling sets is developed to locate attractors and unstable in- variant sets with high degree of accuracy, which can start with a coarse cell structure. A nonuniformly interior-and-boundary sampling technique is used to make the refinement robust. For homeomorphic dissipative dynamical systems, a controlled boundary sampling technique is presented to make gen- eralized cell mapping method with refinement extremely accurate to obtain invariant sets. Recursive laws of group absorption probability and expected absorption time are introduced into generalized cell mapping, and then an optimal order for quantitative analysis of transient cells is established, which leads to the minimal computational work. The improved method is applied to four examples to show its effectiveness in global analysis of dynamical systems.

  12. KNOWLEDGE AND XML BASED CAPP SYSTEM

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shijie; SONG Laigang

    2006-01-01

    In order to enhance the intelligent level of system and improve the interactivity with other systems, a knowledge and XML based computer aided process planning (CAPP) system is implemented. It includes user management, bill of materials(BOM) management, knowledge based process planning, knowledge management and database maintaining sub-systems. This kind of nesting knowledge representation method the system provided can represent complicated arithmetic and logical relationship to deal with process planning tasks. With the representation and manipulation of XML based technological file, the system solves some important problems in web environment such as information interactive efficiency and refreshing of web page. The CAPP system is written in ASP VBScript, JavaScript, Visual C++ languages and Oracle database. At present, the CAPP system is running in Shenyang Machine Tools. The functions of it meet the requirements of enterprise production.

  13. A systems biology-based approach to deciphering the etiology of steatosis employing patient-derived dermal fibroblasts and iPS cells

    Directory of Open Access Journals (Sweden)

    Justyna eJozefczuk

    2012-09-01

    Full Text Available Nonalcoholic fatty liver disease (NAFLD comprises a broad spectrum of disease states ranging from simple steatosis to nonalcoholic steatohepatitis (NASH. As a result of increases in the prevalences of obesity, insulin resistance, and hyperlipidemia, the number of people with hepatic steatosis continues to increase. Differences in susceptibility to steatohepatitis and its progression to cirrhosis have been attributed to a complex interplay of genetic and external factors all addressing the intracellular network. Increase in sugar or refined carbohydrate consumption results in an increase of insulin and insulin resistance that can lead to the accumulation of fat in the liver. Here we demonstrate how a multidisciplinary approach encompassing cellular reprogramming, transcriptomics, proteomics, metabolomics, modeling, network reconstruction and data management can be employed to unveil the mechanisms underlying the progression of steatosis. Proteomics revealed reduced AKT/mTOR signaling in fibroblasts derived from steatosis patients and further establishes that the insulin-resistant phenotype is present not only in insulin-metabolizing central organs, e.g. the liver, but is also manifested in skin fibroblasts. Transcriptome data enabled the generation of a regulatory network based on the transcription factor SREBF1, linked to a metabolic network of glycerolipid and fatty acid biosynthesis including the downstream transcriptional targets of SREBF1 which include LIPIN1 (LPIN and low density lipoprotein receptor (LDLR. Glutathione metabolism was among the pathways enriched in steatosis patients in comparison to healthy controls. By using a model of the glutathione pathway we predict a significant increase in the flux through glutathione synthesis as both gamma-glutamylcysteine synthetase and glutathione synthetase have an increased flux. We anticipate that a larger sample of patients and matching controls will confirm our preliminary findings presented

  14. Computer-Based Wireless Advertising Communication System

    OpenAIRE

    Anwar Al-Mofleh; Yahya Salameh Khraisat

    2009-01-01

    In this paper we developed a computer based wireless advertising communication system (CBWACS) that enables the user to advertise whatever he wants from his own office to the screen in front of the customer via wireless communication system. This system consists of two PIC microcontrollers, transmitter, receiver, LCD, serial cable and antenna. The main advantages of the system are: the wireless structure and the system is less susceptible to noise and other interferences because it uses digit...

  15. Computer-Based Wireless Advertising Communication System

    Directory of Open Access Journals (Sweden)

    Anwar Al-Mofleh

    2009-10-01

    Full Text Available In this paper we developed a computer based wireless advertising communication system (CBWACS that enables the user to advertise whatever he wants from his own office to the screen in front of the customer via wireless communication system. This system consists of two PIC microcontrollers, transmitter, receiver, LCD, serial cable and antenna. The main advantages of the system are: the wireless structure and the system is less susceptible to noise and other interferences because it uses digital communication techniques.

  16. Signal transduction in cells of the immune system in microgravity

    Directory of Open Access Journals (Sweden)

    Huber Kathrin

    2008-10-01

    Full Text Available Abstract Life on Earth developed in the presence and under the constant influence of gravity. Gravity has been present during the entire evolution, from the first organic molecule to mammals and humans. Modern research revealed clearly that gravity is important, probably indispensable for the function of living systems, from unicellular organisms to men. Thus, gravity research is no more or less a fundamental question about the conditions of life on Earth. Since the first space missions and supported thereafter by a multitude of space and ground-based experiments, it is well known that immune cell function is severely suppressed in microgravity, which renders the cells of the immune system an ideal model organism to investigate the influence of gravity on the cellular and molecular level. Here we review the current knowledge about the question, if and how cellular signal transduction depends on the existence of gravity, with special focus on cells of the immune system. Since immune cell function is fundamental to keep the organism under imnological surveillance during the defence against pathogens, to investigate the effects and possible molecular mechanisms of altered gravity is indispensable for long-term space flights to Earth Moon or Mars. Thus, understanding the impact of gravity on cellular functions on Earth will provide not only important informations about the development of life on Earth, but also for therapeutic and preventive strategies to cope successfully with medical problems during space exploration.

  17. Phase Space Cell in Nonextensive Classical Systems

    Directory of Open Access Journals (Sweden)

    Piero Quarati

    2003-06-01

    Full Text Available Abstract: We calculate the phase space volume Ω occupied by a nonextensive system of N classical particles described by an equilibrium (or steady-state, or long-term stationary state of a nonequilibrium system distribution function, which slightly deviates from Maxwell-Boltzmann (MB distribution in the high energy tail. We explicitly require that the number of accessible microstates does not change respect to the extensive MB case. We also derive, within a classical scheme, an analytical expression of the elementary cell that can be seen as a macrocell, different from the third power of Planck constant. Thermodynamic quantities like entropy, chemical potential and free energy of a classical ideal gas, depending on elementary cell, are evaluated. Considering the fractional deviation from MB distribution we can deduce a physical meaning of the nonextensive parameter q of the Tsallis nonextensive thermostatistics in terms of particle correlation functions (valid at least in the case, discussed in this work, of small deviations from MB standard case.

  18. Status of commercial fuel cell powerplant system development

    Science.gov (United States)

    Warshay, Marvin

    The primary focus is on the development of commercial Phosphoric Acid Fuel Cell (PAFC) powerplant systems because the PAFC, which has undergone extensive development, is currently the closest fuel cell system to commercialization. Shorter discussions are included on the high temperature fuel cell systems which are not as mature in their development, such as the Molten Carbonate Fuel Cell (MCFC) and the Solid Oxide Fuel Cell (SOFC). The alkaline and the Solid Polymer Electrolyte (SPE) fuel cell systems, are also included, but their discussions are limited to their prospects for commercial development. Currently, although the alkaline fuel cell continues to be used for important space applications there are no commercial development programs of significant size in the USA and only small efforts outside. The market place for fuel cells and the status of fuel cell programs in the USA receive extensive treatment. The fuel cell efforts outside the USA, especially the large Japanese programs, are also discussed.

  19. Web-Based Evaluation System for Learning Management Systems

    Science.gov (United States)

    Momani, Alaa

    2010-01-01

    E-learning systems have become an issue in recent years. A learning management system (LMS) is an electronic environment helps the educational society to communicate, exchange information, manage, and schedule the learning process. This study has provided a web-based evaluation system that may help the users to choose the convenient system…

  20. MR-based imaging of neural stem cells

    International Nuclear Information System (INIS)

    The efficacy of therapies based on neural stem cells (NSC) has been demonstrated in preclinical models of several central nervous system (CNS) diseases. Before any potential human application of such promising therapies can be envisaged, there are some important issues that need to be solved. The most relevant one is the requirement for a noninvasive technique capable of monitoring NSC delivery, homing to target sites and trafficking. Knowledge of the location and temporospatial migration of either transplanted or genetically modified NSC is of the utmost importance in analyzing mechanisms of correction and cell distribution. Further, such a technique may represent a crucial step toward clinical application of NSC-based approaches in humans, for both designing successful protocols and monitoring their outcome. Among the diverse imaging approaches available for noninvasive cell tracking, such as nuclear medicine techniques, fluorescence and bioluminescence, magnetic resonance imaging (MRI) has unique advantages. Its high temporospatial resolution, high sensitivity and specificity render MRI one of the most promising imaging modalities available, since it allows dynamic visualization of migration of transplanted cells in animal models and patients during clinically useful time periods. Different cellular and molecular labeling approaches for MRI depiction of NSC are described and discussed in this review, as well as the most relevant issues to be considered in optimizing molecular imaging techniques for clinical application. (orig.)

  1. The cell monolayer trajectory from the system state point of view.

    Science.gov (United States)

    Stys, Dalibor; Vanek, Jan; Nahlik, Tomas; Urban, Jan; Cisar, Petr

    2011-10-01

    Time-lapse microscopic movies are being increasingly utilized for understanding the derivation of cell states and predicting cell future. Often, fluorescence and other types of labeling are not available or desirable, and cell state-definitions based on observable structures must be used. We present the methodology for cell behavior recognition and prediction based on the short term cell recurrent behavior analysis. This approach has theoretical justification in non-linear dynamics theory. The methodology is based on the general stochastic systems theory which allows us to define the cell states, trajectory and the system itself. We introduce the usage of a novel image content descriptor based on information contribution (gain) by each image point for the cell state characterization as the first step. The linkage between the method and the general system theory is presented as a general frame for cell behavior interpretation. We also discuss extended cell description, system theory and methodology for future development. This methodology may be used for many practical purposes, ranging from advanced, medically relevant, precise cell culture diagnostics to very utilitarian cell recognition in a noisy or uneven image background. In addition, the results are theoretically justified. PMID:21879106

  2. The cell monolayer trajectory from the system state point of view.

    Science.gov (United States)

    Stys, Dalibor; Vanek, Jan; Nahlik, Tomas; Urban, Jan; Cisar, Petr

    2011-10-01

    Time-lapse microscopic movies are being increasingly utilized for understanding the derivation of cell states and predicting cell future. Often, fluorescence and other types of labeling are not available or desirable, and cell state-definitions based on observable structures must be used. We present the methodology for cell behavior recognition and prediction based on the short term cell recurrent behavior analysis. This approach has theoretical justification in non-linear dynamics theory. The methodology is based on the general stochastic systems theory which allows us to define the cell states, trajectory and the system itself. We introduce the usage of a novel image content descriptor based on information contribution (gain) by each image point for the cell state characterization as the first step. The linkage between the method and the general system theory is presented as a general frame for cell behavior interpretation. We also discuss extended cell description, system theory and methodology for future development. This methodology may be used for many practical purposes, ranging from advanced, medically relevant, precise cell culture diagnostics to very utilitarian cell recognition in a noisy or uneven image background. In addition, the results are theoretically justified.

  3. Setting up Linux based network system

    OpenAIRE

    Karki, Sanjeeb

    2012-01-01

    The goal of the project was to build a Linux based network system where clients get full benefit of various services. The project was implemented at Isokyrö 61500, Finland. The project contains various network system implementations such as File server, Webcam server and Asterisk server. The thesis implements the understanding of the network systems into real use. Configuration of File server consist the security of each user based on the users need and handling their permissions. The netw...

  4. Mesenchymal stem cell-based therapy for type 1 diabetes.

    Science.gov (United States)

    Wu, Hao; Mahato, Ram I

    2014-03-01

    Diabetes has increasingly become a worldwide health problem, causing huge burden on healthcare system and economy. Type 1 diabetes (T1D), traditionally termed "juvenile diabetes" because of an early onset age, is affecting 5-10% of total diabetic population. Insulin injection, the predominant treatment for T1D, is effective to ameliorate the hyperglycemia but incompetent to relieve the autoimmunity and to regenerate lost islets. Islet transplantation, an experimental treatment for T1D, also suffers from limited supply of human islets and poor immunosuppression. The recent progress in regenerative medicine, especially stem cell therapy, has suggested several novel and potential cures for T1D. Mesenchymal stem cell (MSC) based cell therapy is among one of them. MSCs are a type of adult stem cells residing in bone marrow, adipose tissue, umbilical cord blood, and many other tissues. MSCs, with self-renewal potential and transdifferentiation capability, can be expanded in vitro and directed to various cell lineages with relatively less efforts. MSCs have well-characterized hypoimmunogenicity and immunomodulatory effect. All these features make MSCs attractive for treating T1D. Here, we review the properties of MSCs and some of the recent progress using MSCs as a new therapeutic in the treatment of T1D. We also discuss the strength and limitations of using MSC therapy in human trials.

  5. Knowledge Based Systems and Metacognition in Radar

    Science.gov (United States)

    Capraro, Gerard T.; Wicks, Michael C.

    An airborne ground looking radar sensor's performance may be enhanced by selecting algorithms adaptively as the environment changes. A short description of an airborne intelligent radar system (AIRS) is presented with a description of the knowledge based filter and detection portions. A second level of artificial intelligence (AI) processing is presented that monitors, tests, and learns how to improve and control the first level. This approach is based upon metacognition, a way forward for developing knowledge based systems.

  6. Fuel-Cell Power Source Based on Onboard Rocket Propellants

    Science.gov (United States)

    Ganapathi, Gani; Narayan, Sri

    2010-01-01

    The use of onboard rocket propellants (dense liquids at room temperature) in place of conventional cryogenic fuel-cell reactants (hydrogen and oxygen) eliminates the mass penalties associated with cryocooling and boil-off. The high energy content and density of the rocket propellants will also require no additional chemical processing. For a 30-day mission on the Moon that requires a continuous 100 watts of power, the reactant mass and volume would be reduced by 15 and 50 percent, respectively, even without accounting for boiloff losses. The savings increase further with increasing transit times. A high-temperature, solid oxide, electrolyte-based fuel-cell configuration, that can rapidly combine rocket propellants - both monopropellant system with hydrazine and bi-propellant systems such as monomethyl hydrazine/ unsymmetrical dimethyl hydrazine (MMH/UDMH) and nitrogen tetroxide (NTO) to produce electrical energy - overcomes the severe drawbacks of earlier attempts in 1963-1967 of using fuel reforming and aqueous media. The electrical energy available from such a fuel cell operating at 60-percent efficiency is estimated to be 1,500 Wh/kg of reactants. The proposed use of zirconia-based oxide electrolyte at 800-1,000 C will permit continuous operation, very high power densities, and substantially increased efficiency of conversion over any of the earlier attempts. The solid oxide fuel cell is also tolerant to a wide range of environmental temperatures. Such a system is built for easy refueling for exploration missions and for the ability to turn on after several years of transit. Specific examples of future missions are in-situ landers on Europa and Titan that will face extreme radiation and temperature environments, flyby missions to Saturn, and landed missions on the Moon with 14 day/night cycles.

  7. PRESSURIZED SOLID OXIDE FUEL CELL/GAS TURBINE POWER SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    W.L. Lundberg; G.A. Israelson; R.R. Moritz(Rolls-Royce Allison); S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann (Consultant)

    2000-02-01

    Power systems based on the simplest direct integration of a pressurized solid oxide fuel cell (SOFC) generator and a gas turbine (GT) are capable of converting natural gas fuel energy to electric power with efficiencies of approximately 60% (net AC/LHV), and more complex SOFC and gas turbine arrangements can be devised for achieving even higher efficiencies. The results of a project are discussed that focused on the development of a conceptual design for a pressurized SOFC/GT power system that was intended to generate 20 MWe with at least 70% efficiency. The power system operates baseloaded in a distributed-generation application. To achieve high efficiency, the system integrates an intercooled, recuperated, reheated gas turbine with two SOFC generator stages--one operating at high pressure, and generating power, as well as providing all heat needed by the high-pressure turbine, while the second SOFC generator operates at a lower pressure, generates power, and provides all heat for the low-pressure reheat turbine. The system cycle is described, major system components are sized, the system installed-cost is estimated, and the physical arrangement of system components is discussed. Estimates of system power output, efficiency, and emissions at the design point are also presented, and the system cost of electricity estimate is developed.

  8. Port-based modeling of mechatronic systems

    NARCIS (Netherlands)

    Breedveld, Peter C.

    2004-01-01

    Many engineering activities, including mechatronic design, require that a multidomain or ‘multi-physics’ system and its control system be designed as an integrated system. This contribution discusses the background and tools for a port-based approach to integrated modeling and simulation of physical

  9. WIRELESS SENSOR NETWORK BASED CONVEYOR SURVEILLANCE SYSTEM

    OpenAIRE

    Attila Trohák; Máté Kolozsi-Tóth; Péter Rádi

    2011-01-01

    In the paper we will introduce an intelligent conveyor surveillance system. We started a research project to design and develop a conveyor surveillance system based on wireless sensor network and GPRS communication. Our system is able to measure temperature on fixed and moving, rotating surfaces and able to detect smoke. We would like to introduce the developed devices and give an application example.

  10. Exploiting the role of endogenous lymphoid-resident dendritic cells in the priming of NKT cells and CD8+ T cells to dendritic cell-based vaccines.

    Directory of Open Access Journals (Sweden)

    Troels R Petersen

    Full Text Available Transfer of antigen between antigen-presenting cells (APCs is potentially a physiologically relevant mechanism to spread antigen to cells with specialized stimulatory functions. Here we show that specific CD8+ T cell responses induced in response to intravenous administration of antigen-loaded bone marrow-derived dendritic cells (BM-DCs, were ablated in mice selectively depleted of endogenous lymphoid-resident langerin+ CD8α+ dendritic cells (DCs, suggesting that the antigen is transferred from the injected cells to resident APCs. In contrast, antigen-specific CD4+ T cells were primed predominantly by the injected BM-DCs, with only very weak contribution of resident APCs. Crucially, resident langerin+ CD8α+ DCs only contributed to the priming of CD8+ T cells in the presence of maturation stimuli such as intravenous injection of TLR ligands, or by loading the BM-DCs with the glycolipid α-galactosylceramide (α-GalCer to recruit the adjuvant activity of activated invariant natural killer-like T (iNKT cells. In fact, injection of α-GalCer-loaded CD1d-/- BM-DCs resulted in potent iNKT cell activation, suggesting that this glycolipid antigen can also be transferred to resident CD1d+ APCs. While iNKT cell activation per se was independent of langerin+ CD8α+ DCs, some iNKT cell-mediated activities were reduced, notably release of IL-12p70 and transactivation of NK cells. We conclude that both protein and glycolipid antigens can be exchanged between distinct DC species. These data suggest that the efficacy of DC-based vaccination strategies may be improved by the incorporation of a systemic maturation signal aimed to engage resident APCs in CD8+ T cell priming, and α-GalCer may be particularly well suited to this purpose.

  11. Thermodynamic Performance Study of Biomass Gasification, Solid Oxide Fuel Cell and Micro Gas Turbine Hybrid Systems

    DEFF Research Database (Denmark)

    Bang-Møller, Christian; Rokni, Masoud

    2010-01-01

    A system level modelling study of three combined heat and power systems based on biomass gasification is presented. Product gas is converted in a micro gas turbine (MGT) in the first system, in a solid oxide fuel cell (SOFC) in the second system and in a combined SOFC–MGT arrangement in the third...

  12. Z - Source Multi Level Inverter Based PV Generation System

    Directory of Open Access Journals (Sweden)

    T. Lakhmi kanth

    2014-09-01

    Full Text Available In this paper a novel technique of Z-Source multilevel Inverter based PV Generation system is implemented and simulated using MATLAB-Simulink simulation software. The Photovoltaic cells are healthier option for converting solar energy into electricity. Due to high capital cost and low efficiency PV cells have not yet been a fully smart choice for electricity users. To enhance the performance of the system, Z-Source multi level inverter can be used in place of conventional Voltage Source Inverter (VSI in Solar Power Generation System. The PV cell model is developed using circuit mathematical equations. The Z-Source multilevel inverter is modeled to realize boosted DC to AC conversion (inversion with low THD. Outcome shows that the energy conversion efficiency of ZSMLI is a lot improved as compared to conventional voltage Source Inverter (VSI. By doing FFT analysis we can know the total THD.

  13. GCtool for fuel cell systems design and analysis : user documentation.

    Energy Technology Data Exchange (ETDEWEB)

    Ahluwalia, R.K.; Geyer, H.K.

    1999-01-15

    GCtool is a comprehensive system design and analysis tool for fuel cell and other power systems. A user can analyze any configuration of component modules and flows under steady-state or dynamic conditions. Component models can be arbitrarily complex in modeling sophistication and new models can be added easily by the user. GCtool also treats arbitrary system constraints over part or all of the system, including the specification of nonlinear objective functions to be minimized subject to nonlinear, equality or inequality constraints. This document describes the essential features of the interpreted language and the window-based GCtool environment. The system components incorporated into GCtool include a gas flow mixer, splitier, heater, compressor, gas turbine, heat exchanger, pump, pipe, diffuser, nozzle, steam drum, feed water heater, combustor, chemical reactor, condenser, fuel cells (proton exchange membrane, solid oxide, phosphoric acid, and molten carbonate), shaft, generator, motor, and methanol steam reformer. Several examples of system analysis at various levels of complexity are presented. Also given are instructions for generating two- and three-dimensional plots of data and the details of interfacing new models to GCtool.

  14. Fluidized bed control system based on inverse system method

    Institute of Scientific and Technical Information of China (English)

    SONG Fu-hua; LI Ping

    2005-01-01

    The invertible of the Large Air Dense Medium Fluidized Bed (ADMFB) were studied by introducing the concept of the inverse system theory of nonlinear systems.Then the ADMFB, which was a multivariable, nonlinear and coupled strongly system,was decoupled into independent SISO pseudo-linear subsystems. Linear controllers were designed for each of subsystems based on linear systems theory. The practice output proves that this method improves the stability of the ADMFB obviously.

  15. Drug delivery system and breast cancer cells

    Science.gov (United States)

    Colone, Marisa; Kaliappan, Subramanian; Calcabrini, Annarica; Tortora, Mariarosaria; Cavalieri, Francesca; Stringaro, Annarita

    2016-06-01

    Recently, nanomedicine has received increasing attention for its ability to improve the efficacy of cancer therapeutics. Nanosized polymer therapeutic agents offer the advantage of prolonged circulation in the blood stream, targeting to specific sites, improved efficacy and reduced side effects. In this way, local, controlled delivery of the drug will be achieved with the advantage of a high concentration of drug release at the target site while keeping the systemic concentration of the drug low, thus reducing side effects due to bioaccumulation. Various drug delivery systems such as nanoparticles, liposomes, microparticles and implants have been demonstrated to significantly enhance the preventive/therapeutic efficacy of many drugs by increasing their bioavailability and targetability. As these carriers significantly increase the therapeutic effect of drugs, their administration would become less cost effective in the near future. The purpose of our research work is to develop a delivery system for breast cancer cells using a microvector of drugs. These results highlight the potential uses of these responsive platforms suited for biomedical and pharmaceutical applications. At the request of all authors of the paper an updated version was published on 12 July 2016. The manuscript was prepared and submitted without Dr. Francesca Cavalieri's contribution and her name was added without her consent. Her name has been removed in the updated and re-published article.

  16. Fuzzy Case-Based Reasoning System

    Directory of Open Access Journals (Sweden)

    Jing Lu

    2016-06-01

    Full Text Available In this paper, we propose a fuzzy case-based reasoning system, using a case-based reasoning (CBR system that learns from experience to solve problems. Different from a traditional case-based reasoning system that uses crisp cases, our system works with fuzzy ones. Specifically, we change a crisp case into a fuzzy one by fuzzifying each crisp case element (feature, according to the maximum degree principle. Thus, we add the “vague” concept into a case-based reasoning system. It is these somewhat vague inputs that make the outcomes of the prediction more meaningful and accurate, which illustrates that it is not necessarily helpful when we always create accurate predictive relations through crisp cases. Finally, we prove this and apply this model to practical weather forecasting, and experiments show that using fuzzy cases can make some prediction results more accurate than using crisp cases.

  17. Model Based Testing for Agent Systems

    Science.gov (United States)

    Zhang, Zhiyong; Thangarajah, John; Padgham, Lin

    Although agent technology is gaining world wide popularity, a hindrance to its uptake is the lack of proper testing mechanisms for agent based systems. While many traditional software testing methods can be generalized to agent systems, there are many aspects that are different and which require an understanding of the underlying agent paradigm. In this paper we present certain aspects of a testing framework that we have developed for agent based systems. The testing framework is a model based approach using the design models of the Prometheus agent development methodology. In this paper we focus on model based unit testing and identify the appropriate units, present mechanisms for generating suitable test cases and for determining the order in which the units are to be tested, present a brief overview of the unit testing process and an example. Although we use the design artefacts from Prometheus the approach is suitable for any plan and event based agent system.

  18. Use of viral promoters in mammalian cell-based bioassays: How reliable?

    OpenAIRE

    Gill-Sharma Manjit; Choudhuri Jyoti; Betrabet Shrikant S

    2004-01-01

    Abstract Cell-based bioassays have been suggested for screening of hormones and drug bioactivities. They are a plausible alternative to animal based methods. The technique used is called receptor/reporter system. Receptor/reporter system was initially developed as a research technique to understand gene function. Often reporter constructs containing viral promoters were used because they could be expressed with very 'high' magnitude in a variety of cell types in the laboratory. On the other h...

  19. Dendritic cell-based cancer immunotherapy for colorectal cancer.

    Science.gov (United States)

    Kajihara, Mikio; Takakura, Kazuki; Kanai, Tomoya; Ito, Zensho; Saito, Keisuke; Takami, Shinichiro; Shimodaira, Shigetaka; Okamoto, Masato; Ohkusa, Toshifumi; Koido, Shigeo

    2016-05-01

    Colorectal cancer (CRC) is one of the most common cancers and a leading cause of cancer-related mortality worldwide. Although systemic therapy is the standard care for patients with recurrent or metastatic CRC, the prognosis is extremely poor. The optimal sequence of therapy remains unknown. Therefore, alternative strategies, such as immunotherapy, are needed for patients with advanced CRC. This review summarizes evidence from dendritic cell-based cancer immunotherapy strategies that are currently in clinical trials. In addition, we discuss the possibility of antitumor immune responses through immunoinhibitory PD-1/PD-L1 pathway blockade in CRC patients. PMID:27158196

  20. Photo electrochemical and organic-based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, N.S. [California Institute of Technology, Pasadena, CA (United States); Kamat, P. [Univ. of Notre Dame, IN (United States); Spitler, M. [Boston Univ., MA (United States)

    1996-09-01

    Research in solar photoconversion has resulted in significant advances in the fields of photoelectrochemistry and dye-sensitized solar cells. Progress is also evident in the understanding of solid state organic systems for energy transduction. It is evident, however, that the examination in this report of the accomplishments in these areas serves to highlight the great extent of research that is necessary to establish a technology base sufficient for practical application. Recommendations are made in this report on the directions that this research should take.

  1. Dendritic cell-based cancer immunotherapy for colorectal cancer.

    Science.gov (United States)

    Kajihara, Mikio; Takakura, Kazuki; Kanai, Tomoya; Ito, Zensho; Saito, Keisuke; Takami, Shinichiro; Shimodaira, Shigetaka; Okamoto, Masato; Ohkusa, Toshifumi; Koido, Shigeo

    2016-05-01

    Colorectal cancer (CRC) is one of the most common cancers and a leading cause of cancer-related mortality worldwide. Although systemic therapy is the standard care for patients with recurrent or metastatic CRC, the prognosis is extremely poor. The optimal sequence of therapy remains unknown. Therefore, alternative strategies, such as immunotherapy, are needed for patients with advanced CRC. This review summarizes evidence from dendritic cell-based cancer immunotherapy strategies that are currently in clinical trials. In addition, we discuss the possibility of antitumor immune responses through immunoinhibitory PD-1/PD-L1 pathway blockade in CRC patients.

  2. Simulation based design of automotive systems

    OpenAIRE

    Schiehlen, Werner

    1993-01-01

    The design of automotive systems using simulation tools features cost reduction and quality enhancement. This paper presents two basic approaches. The rust approach deals with the application of CAD data bases to the evaluation of input data for multibody system formalisms, most adequate for automotive system modeling. An object oriented data model for multibody systems is presented. The second approach covers the development of an integrated simulation tool for automotive vehicles and the co...

  3. Hybrid regenerative fuel cell systems for space applications

    Science.gov (United States)

    Saucier, David R.

    1988-01-01

    This paper describes a hybrid regenerative fuel cell (RFC) system for space application, which is made up of an alkaline fuel cell (Space Shuttle fuel cell) and an acid electrolysis unit (solid polymer electrolyte). In the RFC, gas produced from the acid electrolysis unit and water produced by the alkaline fuel cell are repeatedly reacted in the other unit. The results of RFC's tests indicate that the system is feasible in terms of fluid/unit compatibility. In addition, the fuel cell thermal-control system proved capable of controlling fuel cell temperatures throughout long open-circuit periods. Diagrams of the RFC and its subsystems are included.

  4. Component Based Dynamic Reconfigurable Test System

    Institute of Scientific and Technical Information of China (English)

    LAI Hong; HE Lingsong; ZHANG Dengpan

    2006-01-01

    In this paper, a novel component based framework of test system is presented for the new requirements of dynamic changes of test functions and reconfiguration of test resources. The complexity of dynamic reconfiguration arises from the scale, redirection, extensibility and interconnection of components in test system. The paper is started by discussing the component assembly based framework which provide the open platform to the deploy of components and then the script interpreter model is introduced to dynamically create the components and build the test system by analyzing XML based information of test system. A pipeline model is presented to provide the data channels and behavior reflection among the components. Finally, a dynamic reconfigurable test system is implemented on the basis of COM and applied in the remote test and control system of CNC machine.

  5. FPGA-Based Plant Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yoon Hee; Ha, Jae Hong; Kim, Hang Bae [KEPCO E and C, Daejeon (Korea, Republic of)

    2011-08-15

    This paper relates to a plant protection system which detects non-permissible conditions and determines initiation of protective actions for nuclear power plants (NPPs). Conventional plant protection systems were designed based on analog technologies. It is well known that existing protection systems for NPPs contain many components which are becoming obsolete at an increasing rate. Nowadays maintenance and repair for analog-based plant protection systems may be difficult as analog parts become obsolete or difficult to obtain. Accordingly, as an alternative to the analog technology, the digitalisation of the plant protection system was required. Recently digital plant protection systems which include programmable logic controllers (PLCs) and/or computers have been introduced. However PLC or computer-based plant protection systems use an operating system and application software, and so they may result in a common mode failure when a problem occurs in the operating system or application software. Field Programmable Gate Arrays (FPGAs) are highlighted as an alternative to conventional protection or control systems. The paper presents the design of a four-channel plant protection system whose protection functions are implemented in FPGAs without any central processing unit or operating system.

  6. Distributed Monitoring System Based on ICINGA

    CERN Multimedia

    Haen, C; Neufeld, N

    2011-01-01

    The LHCb online system relies on a large and heterogeneous I.T. infrastructure : it comprises more than 2000 servers and embedded systems and more than 200 network devices. While for the control and monitoring of detectors, PLCs, and readout boards an industry standard SCADA system PVSSII has been put in production, we use a low level monitoring system to monitor the control infrastructure itself. While our previous system was based on a single central NAGIOS server, our current system uses a distributed ICINGA infrastructure.

  7. Aquaporin-4 autoantibodies in neuromyelitis optica spectrum disorders: comparison between tissue-based and cell-based indirect immunofluorescence assays

    Directory of Open Access Journals (Sweden)

    Chan Koon H

    2010-09-01

    Full Text Available Abstract Background Neuromyelitis optica spectrum disorders (NMOSD are severe central nervous system inflammatory demyelinating disorders (CNS IDD characterized by monophasic or relapsing, longitudinally extensive transverse myelitis (LETM and/or optic neuritis (ON. A significant proportion of NMOSD patients are seropositive for aquaporin-4 (AQP4 autoantibodies. We compared the AQP4 autoantibody detection rates of tissue-based indirect immunofluorescence assay (IIFA and cell-based IIFA. Methods Serum of Chinese CNS IDD patients were assayed for AQP4 autoantibodies by tissue-based IIFA using monkey cerebellum and cell-based IIFA using transfected HEK293 cells which express human AQP4 on their cell membranes. Results In total, 128 CNS IDD patients were studied. We found that 78% of NMO patients were seropositive for AQP4 autoantibodies by cell-based IIFA versus 61% by tissue-based IFA (p = 0.250, 75% of patients having relapsing myelitis (RM with LETM were seropositive by cell-based IIFA versus 50% by tissue-based IIFA (p = 0.250, and 33% of relapsing ON patients were seropositive by cell-based IIFA versus 22% by tissue-based IIFA (p = 1.000; however the differences were not statistically significant. All patients seropositive by tissue-based IIFA were also seropositive for AQP4 autoantibodies by cell-based IIFA. Among 29 NMOSD patients seropositive for AQP4 autoantibodies by cell-based IIFA, 20 (69% were seropositive by tissue-based IIFA. The 9 patients seropositive by cell-based IIFA while seronegative by tissue-based IIFA had NMO (3, RM with LETM (3, a single attack of LETM (1, relapsing ON (1 and a single ON attack (1. Among 23 NMO or RM patients seropositive for AQP4 autoantibodies by cell-based IIFA, comparison between those seropositive (n = 17 and seronegative (n = 6 by tissue-based IIFA revealed no differences in clinical and neuroradiological characteristics between the two groups. Conclusion Cell-based IIFA is slightly more sensitive

  8. Simplified Load-Following Control for a Fuel Cell System

    Science.gov (United States)

    Vasquez, Arturo

    2010-01-01

    A simplified load-following control scheme has been proposed for a fuel cell power system. The scheme could be used to control devices that are important parts of a fuel cell system but are sometimes characterized as parasitic because they consume some of the power generated by the fuel cells.

  9. A Physics-based Analytical Model for Perovskite Solar Cells

    OpenAIRE

    Sun, Xingshu; Asadpour, Reza; Nie, Wanyi; Mohite, Aditya D.; Alam, Muhammad A.

    2015-01-01

    Perovskites are promising next-generation absorber materials for low-cost and high-efficiency solar cells. Although perovskite cells are configured similar to the classical solar cells, their operation is unique and requires development of a new physical model for characterization, optimization of the cells, and prediction of the panel performance. In this paper, we develop such a physics-based analytical model to describe the operation of different types of perovskite solar cells, explicitly...

  10. Microfluidic-based single cell trapping using a combination of stagnation point flow and physical barrier

    Science.gov (United States)

    Yu, Miao; Chen, Zongzheng; Xiang, Cheng; Liu, Bo; Xie, Handi; Qin, Kairong

    2016-06-01

    Single cell trapping in vitro by microfluidic device is an emerging approach for the study of the relationship between single cells and their dynamic biochemical microenvironments. In this paper, a hydrodynamic-based microfluidic device for single cell trapping is designed using a combination of stagnation point flow and physical barrier. The microfluidic device overcomes the weakness of the traditional ones, which have been only based upon either stagnation point flows or physical barriers, and can conveniently load dynamic biochemical signals to the trapped cell. In addition, it can connect with a programmable syringe pump and a microscope to constitute an integrated experimental system. It is experimentally verified that the microfluidic system can trap single cells in vitro even under flow disturbance and conveniently load biochemical signals to the trapped cell. The designed micro-device would provide a simple yet effective experimental platform for further study of the interactions between single cells and their microenvironments.

  11. Gravisensing in single-celled systems: characean rhizoids and protonemata

    Science.gov (United States)

    Braun, M.

    Gravitropically tip-growing cell types are attractive unicellular model systems for investigating the mechanisms and the regulation of gravitropism. Especially useful for studying the mechanisms of positive and negative gravitropic tip-growth are characean rhizoids and protonemata. They originate from the same cell type, show the same overall cell shape, cytoplasmic zonation, arrangement of actin and microtubule cytoskeleton, use statoliths for gravisensing, but show opposite gravitropism. In both cell types, actin microfilaments are complexly organized in the apical dome, where a dense spherical actin array is colocalized with spectrin-like epitopes and a unique endoplasmic reticulum aggregate, the structural center of the Spitzenkörper. The opposite gravitropic responses seem to be based on differences in the actin-organized anchorage of the Spitzenkörper and the actin-mediated transport of statoliths. In negatively gravitropic (upward bending) protonemata, the statoliths-induced drastic upward shift of the cell tip is preceded by a relocalization of dihydropyridine-binding calcium channels and of the apical calcium gradient to the upper flank (bending by bulging). Such relocalizations have not been observed in positively gravitropically responding (downward growing) rhizoids in which statoliths sedimentation is followed by differential flank growth (bending by bowing). This paper reviews the current knowledge and hypotheses on the mechanisms of the opposite gravitropic responses in characean rhizoids and protonemata.

  12. Multiplexed labeling system for high-throughput cell sorting.

    Science.gov (United States)

    Shin, Seung Won; Park, Kyung Soo; Song, In Hyun; Shin, Woo Jung; Kim, Byung Woo; Kim, Dong-Ik; Um, Soong Ho

    2016-09-01

    Flow cytometry and fluorescence activated cell sorting techniques were designed to realize configurable classification and separation of target cells. A number of cell phenotypes with different functionalities have recently been revealed. Before simultaneous selective capture of cells, it is desirable to label different samples with the corresponding dyes in a multiplexing manner to allow for a single analysis. However, few methods to obtain multiple fluorescent colors for various cell types have been developed. Even when restricted laser sources are employed, a small number of color codes can be expressed simultaneously. In this study, we demonstrate the ability to manifest DNA nanostructure-based multifluorescent colors formed by a complex of dyes. Highly precise self-assembly of fluorescent dye-conjugated oligonucleotides gives anisotropic DNA nanostructures, Y- and tree-shaped DNA (Y-DNA and T-DNA, respectively), which may be used as platforms for fluorescent codes. As a proof of concept, we have demonstrated seven different fluorescent codes with only two different fluorescent dyes using T-DNA. This method provides maximum efficiency for current flow cytometry. We are confident that this system will provide highly efficient multiplexed fluorescent detection for bioanalysis compared with one-to-one fluorescent correspondence for specific marker detection. PMID:27181032

  13. A Well-Controlled Experimental System to Study Interactions of Cytotoxic T Lymphocytes with Tumor Cells.

    Science.gov (United States)

    Neubert, Natalie J; Soneson, Charlotte; Barras, David; Baumgaertner, Petra; Rimoldi, Donata; Delorenzi, Mauro; Fuertes Marraco, Silvia A; Speiser, Daniel E

    2016-01-01

    While T cell-based immunotherapies are steadily improving, there are still many patients who progress, despite T cell-infiltrated tumors. Emerging evidence suggests that T cells themselves may provoke immune escape of cancer cells. Here, we describe a well-controlled co-culture system for studying the dynamic T cell - cancer cell interplay, using human melanoma as a model. We explain starting material, controls, and culture parameters to establish reproducible and comparable cultures with highly heterogeneous tumor cells. Low passage melanoma cell lines and melanoma-specific CD8+ T cell clones generated from patient blood were cultured together for up to 3 days. Living melanoma cells were isolated from the co-culture system by fluorescence-activated cell sorting. We demonstrate that the characterization of isolated melanoma cells is feasible using flow cytometry for protein expression analysis as well as an Agilent whole human genome microarray and the NanoString technology for differential gene expression analysis. In addition, we identify five genes (ALG12, GUSB, RPLP0, KRBA2, and ADAT2) that are stably expressed in melanoma cells independent of the presence of T cells or the T cell-derived cytokines IFNγ and TNFα. These genes are essential for correct normalization of gene expression data by NanoString. Further to the characterization of melanoma cells after exposure to CTLs, this experimental system might be suitable to answer a series of questions, including how the affinity of CTLs for their target antigen influences the melanoma cell response and whether CTL-induced gene expression changes in melanoma cells are reversible. Taken together, our human T cell - melanoma cell culture system is well suited to characterize immune-related mechanisms in cancer cells.

  14. Cell-Based Odorant Sensor Array for Odor Discrimination Based on Insect Odorant Receptors.

    Science.gov (United States)

    Termtanasombat, Maneerat; Mitsuno, Hidefumi; Misawa, Nobuo; Yamahira, Shinya; Sakurai, Takeshi; Yamaguchi, Satoshi; Nagamune, Teruyuki; Kanzaki, Ryohei

    2016-07-01

    The olfactory system of living organisms can accurately discriminate numerous odors by recognizing the pattern of activation of several odorant receptors (ORs). Thus, development of an odorant sensor array based on multiple ORs presents the possibility of mimicking biological odor discrimination mechanisms. Recently, we developed novel odorant sensor elements with high sensitivity and selectivity based on insect OR-expressing Sf21 cells that respond to target odorants by displaying increased fluorescence intensity. Here we introduce the development of an odorant sensor array composed of several Sf21 cell lines expressing different ORs. In this study, an array pattern of four cell lines expressing Or13a, Or56a, BmOR1, and BmOR3 was successfully created using a patterned polydimethylsiloxane film template and cell-immobilizing reagents, termed biocompatible anchor for membrane (BAM). We demonstrated that BAM could create a clear pattern of Sf21 sensor cells without impacting their odorant-sensing performance. Our sensor array showed odorant-specific response patterns toward both odorant mixtures and single odorant stimuli, allowing us to visualize the presence of 1-octen-3-ol, geosmin, bombykol, and bombykal as an increased fluorescence intensity in the region of Or13a, Or56a, BmOR1, and BmOR3 cell lines, respectively. Therefore, we successfully developed a new methodology for creating a cell-based odorant sensor array that enables us to discriminate multiple target odorants. Our method might be expanded into the development of an odorant sensor capable of detecting a large range of environmental odorants that might become a promising tool used in various applications including the study of insect semiochemicals and food contamination.

  15. Microengineering methods for cell-based microarrays and high-throughput drug-screening applications

    International Nuclear Information System (INIS)

    Screening for effective therapeutic agents from millions of drug candidates is costly, time consuming, and often faces concerns due to the extensive use of animals. To improve cost effectiveness, and to minimize animal testing in pharmaceutical research, in vitro monolayer cell microarrays with multiwell plate assays have been developed. Integration of cell microarrays with microfluidic systems has facilitated automated and controlled component loading, significantly reducing the consumption of the candidate compounds and the target cells. Even though these methods significantly increased the throughput compared to conventional in vitro testing systems and in vivo animal models, the cost associated with these platforms remains prohibitively high. Besides, there is a need for three-dimensional (3D) cell-based drug-screening models which can mimic the in vivo microenvironment and the functionality of the native tissues. Here, we present the state-of-the-art microengineering approaches that can be used to develop 3D cell-based drug-screening assays. We highlight the 3D in vitro cell culture systems with live cell-based arrays, microfluidic cell culture systems, and their application to high-throughput drug screening. We conclude that among the emerging microengineering approaches, bioprinting holds great potential to provide repeatable 3D cell-based constructs with high temporal, spatial control and versatility.

  16. Senescence in Human Mesenchymal Stem Cells: Functional Changes and Implications in Stem Cell-Based Therapy

    Science.gov (United States)

    Turinetto, Valentina; Vitale, Emanuela; Giachino, Claudia

    2016-01-01

    Regenerative medicine is extensively interested in developing cell therapies using mesenchymal stem cells (MSCs), with applications to several aging-associated diseases. For successful therapies, a substantial number of cells are needed, requiring extensive ex vivo cell expansion. However, MSC proliferation is limited and it is quite likely that long-term culture evokes continuous changes in MSCs. Therefore, a substantial proportion of cells may undergo senescence. In the present review, we will first present the phenotypic characterization of senescent human MSCs (hMSCs) and their possible consequent functional alterations. The accumulation of oxidative stress and dysregulation of key differentiation regulatory factors determine decreased differentiation potential of senescent hMSCs. Senescent hMSCs also show a marked impairment in their migratory and homing ability. Finally, many factors present in the secretome of senescent hMSCs are able to exacerbate the inflammatory response at a systemic level, decreasing the immune modulation activity of hMSCs and promoting either proliferation or migration of cancer cells. Considering the deleterious effects that these changes could evoke, it would appear of primary importance to monitor the occurrence of senescent phenotype in clinically expanded hMSCs and to evaluate possible ways to prevent in vitro MSC senescence. An updated critical presentation of the possible strategies for in vitro senescence monitoring and prevention constitutes the second part of this review. Understanding the mechanisms that drive toward hMSC growth arrest and evaluating how to counteract these for preserving a functional stem cell pool is of fundamental importance for the development of efficient cell-based therapeutic approaches. PMID:27447618

  17. Graph Cuts based Image Segmentation using Fuzzy Rule Based System

    OpenAIRE

    Khokher, M. R.; A. Ghafoor; A.M. Siddiqui

    2012-01-01

    This work deals with the segmentation of gray scale, color and texture images using graph cuts. From input image, a graph is constructed using intensity, color and texture profiles of the image simultaneously. Based on the nature of image, a fuzzy rule based system is designed to find the weight that should be given to a specific image feature during graph development. The graph obtained from the fuzzy rule based weighted average of different image features is further used in normalized graph...

  18. Web-based Project Reporting System

    Data.gov (United States)

    US Agency for International Development — Web-PRS is a web-based system that captures financial information and project status information that is sortable by geographical location, pillar, project type and...

  19. Android Based Rush And Drunk Driver Alerting System

    Directory of Open Access Journals (Sweden)

    Tanmoy D. Goswami

    2014-02-01

    Full Text Available The Rush driving and driving after consumption of alcohol is a major cause of road accident worldwide. In this paper we proposed an idea to alert rush and drunk driver at early stage before actual accident take place. Complete system works on a cell phone having software installed in it with some sensor. The program calculates the sensor reading and matches with the pattern already present in system, if match found then an alert will give to driver and also a text message will send to the relative asking for help with location details. This system will design on an android based cell phone. Our proposed system will prevent many accidents to occur and save lives.

  20. Systemic adjuvant therapies in renal cell carcinoma.

    Science.gov (United States)

    Buti, Sebastiano; Bersanelli, Melissa; Donini, Maddalena; Ardizzoni, Andrea

    2012-10-01

    Renal cell carcinoma (RCC) is one of the ten most frequent solid tumors worldwide. Recent innovations in the treatment of metastatic disease have led to new therapeutic approaches being investigated in the adjuvant setting. Observation is the only current standard of care after radical nephrectomy, although there is evidence of efficacy of adjuvant use of vaccine among all the strategies used. This article aims to collect published experiences with systemic adjuvant approaches in RCC and to describe the results of past and ongoing phase III clinical trials in this field. We explored all the systemic treatments, including chemotherapy, immunotherapy and targeted drugs while alternative approaches have also been described. Appropriate selection of patients who would benefit from adjuvant therapies remains a crucial dilemma. Although the international guidelines do not actually recommend any adjuvant treatment after radical surgery for RCC, no conclusions have yet been drawn pending the results of the promising ongoing clinical trials with the target therapies. The significant changes that these new drugs have made on advanced disease outcome could represent the key to innovation in terms of preventing recurrence, delaying relapse and prolonging survival after radical surgery for RCC. PMID:25992216